1 /*-------------------------------------------------------------------------
2 *
3 * createplan.c
4 * Routines to create the desired plan for processing a query.
5 * Planning is complete, we just need to convert the selected
6 * Path into a Plan.
7 *
8 * Portions Copyright (c) 1996-2017, PostgreSQL Global Development Group
9 * Portions Copyright (c) 1994, Regents of the University of California
10 *
11 *
12 * IDENTIFICATION
13 * src/backend/optimizer/plan/createplan.c
14 *
15 *-------------------------------------------------------------------------
16 */
17 #include "postgres.h"
18
19 #include <limits.h>
20 #include <math.h>
21
22 #include "access/sysattr.h"
23 #include "catalog/pg_class.h"
24 #include "foreign/fdwapi.h"
25 #include "miscadmin.h"
26 #include "nodes/extensible.h"
27 #include "nodes/makefuncs.h"
28 #include "nodes/nodeFuncs.h"
29 #include "optimizer/clauses.h"
30 #include "optimizer/cost.h"
31 #include "optimizer/paramassign.h"
32 #include "optimizer/paths.h"
33 #include "optimizer/placeholder.h"
34 #include "optimizer/plancat.h"
35 #include "optimizer/planmain.h"
36 #include "optimizer/predtest.h"
37 #include "optimizer/restrictinfo.h"
38 #include "optimizer/subselect.h"
39 #include "optimizer/tlist.h"
40 #include "optimizer/var.h"
41 #include "parser/parse_clause.h"
42 #include "parser/parsetree.h"
43 #include "utils/lsyscache.h"
44
45
46 /*
47 * Flag bits that can appear in the flags argument of create_plan_recurse().
48 * These can be OR-ed together.
49 *
50 * CP_EXACT_TLIST specifies that the generated plan node must return exactly
51 * the tlist specified by the path's pathtarget (this overrides both
52 * CP_SMALL_TLIST and CP_LABEL_TLIST, if those are set). Otherwise, the
53 * plan node is allowed to return just the Vars and PlaceHolderVars needed
54 * to evaluate the pathtarget.
55 *
56 * CP_SMALL_TLIST specifies that a narrower tlist is preferred. This is
57 * passed down by parent nodes such as Sort and Hash, which will have to
58 * store the returned tuples.
59 *
60 * CP_LABEL_TLIST specifies that the plan node must return columns matching
61 * any sortgrouprefs specified in its pathtarget, with appropriate
62 * ressortgroupref labels. This is passed down by parent nodes such as Sort
63 * and Group, which need these values to be available in their inputs.
64 */
65 #define CP_EXACT_TLIST 0x0001 /* Plan must return specified tlist */
66 #define CP_SMALL_TLIST 0x0002 /* Prefer narrower tlists */
67 #define CP_LABEL_TLIST 0x0004 /* tlist must contain sortgrouprefs */
68
69
70 static Plan *create_plan_recurse(PlannerInfo *root, Path *best_path,
71 int flags);
72 static Plan *create_scan_plan(PlannerInfo *root, Path *best_path,
73 int flags);
74 static List *build_path_tlist(PlannerInfo *root, Path *path);
75 static bool use_physical_tlist(PlannerInfo *root, Path *path, int flags);
76 static List *get_gating_quals(PlannerInfo *root, List *quals);
77 static Plan *create_gating_plan(PlannerInfo *root, Path *path, Plan *plan,
78 List *gating_quals);
79 static Plan *create_join_plan(PlannerInfo *root, JoinPath *best_path);
80 static Plan *create_append_plan(PlannerInfo *root, AppendPath *best_path);
81 static Plan *create_merge_append_plan(PlannerInfo *root, MergeAppendPath *best_path,
82 int flags);
83 static Result *create_result_plan(PlannerInfo *root, ResultPath *best_path);
84 static ProjectSet *create_project_set_plan(PlannerInfo *root, ProjectSetPath *best_path);
85 static Material *create_material_plan(PlannerInfo *root, MaterialPath *best_path,
86 int flags);
87 static Plan *create_unique_plan(PlannerInfo *root, UniquePath *best_path,
88 int flags);
89 static Gather *create_gather_plan(PlannerInfo *root, GatherPath *best_path);
90 static Plan *create_projection_plan(PlannerInfo *root, ProjectionPath *best_path);
91 static Plan *inject_projection_plan(Plan *subplan, List *tlist, bool parallel_safe);
92 static Sort *create_sort_plan(PlannerInfo *root, SortPath *best_path, int flags);
93 static Group *create_group_plan(PlannerInfo *root, GroupPath *best_path);
94 static Unique *create_upper_unique_plan(PlannerInfo *root, UpperUniquePath *best_path,
95 int flags);
96 static Agg *create_agg_plan(PlannerInfo *root, AggPath *best_path);
97 static Plan *create_groupingsets_plan(PlannerInfo *root, GroupingSetsPath *best_path);
98 static Result *create_minmaxagg_plan(PlannerInfo *root, MinMaxAggPath *best_path);
99 static WindowAgg *create_windowagg_plan(PlannerInfo *root, WindowAggPath *best_path);
100 static SetOp *create_setop_plan(PlannerInfo *root, SetOpPath *best_path,
101 int flags);
102 static RecursiveUnion *create_recursiveunion_plan(PlannerInfo *root, RecursiveUnionPath *best_path);
103 static void get_column_info_for_window(PlannerInfo *root, WindowClause *wc,
104 List *tlist,
105 int numSortCols, AttrNumber *sortColIdx,
106 int *partNumCols,
107 AttrNumber **partColIdx,
108 Oid **partOperators,
109 int *ordNumCols,
110 AttrNumber **ordColIdx,
111 Oid **ordOperators);
112 static LockRows *create_lockrows_plan(PlannerInfo *root, LockRowsPath *best_path,
113 int flags);
114 static ModifyTable *create_modifytable_plan(PlannerInfo *root, ModifyTablePath *best_path);
115 static Limit *create_limit_plan(PlannerInfo *root, LimitPath *best_path,
116 int flags);
117 static SeqScan *create_seqscan_plan(PlannerInfo *root, Path *best_path,
118 List *tlist, List *scan_clauses);
119 static SampleScan *create_samplescan_plan(PlannerInfo *root, Path *best_path,
120 List *tlist, List *scan_clauses);
121 static Scan *create_indexscan_plan(PlannerInfo *root, IndexPath *best_path,
122 List *tlist, List *scan_clauses, bool indexonly);
123 static BitmapHeapScan *create_bitmap_scan_plan(PlannerInfo *root,
124 BitmapHeapPath *best_path,
125 List *tlist, List *scan_clauses);
126 static Plan *create_bitmap_subplan(PlannerInfo *root, Path *bitmapqual,
127 List **qual, List **indexqual, List **indexECs);
128 static void bitmap_subplan_mark_shared(Plan *plan);
129 static TidScan *create_tidscan_plan(PlannerInfo *root, TidPath *best_path,
130 List *tlist, List *scan_clauses);
131 static SubqueryScan *create_subqueryscan_plan(PlannerInfo *root,
132 SubqueryScanPath *best_path,
133 List *tlist, List *scan_clauses);
134 static FunctionScan *create_functionscan_plan(PlannerInfo *root, Path *best_path,
135 List *tlist, List *scan_clauses);
136 static ValuesScan *create_valuesscan_plan(PlannerInfo *root, Path *best_path,
137 List *tlist, List *scan_clauses);
138 static TableFuncScan *create_tablefuncscan_plan(PlannerInfo *root, Path *best_path,
139 List *tlist, List *scan_clauses);
140 static CteScan *create_ctescan_plan(PlannerInfo *root, Path *best_path,
141 List *tlist, List *scan_clauses);
142 static NamedTuplestoreScan *create_namedtuplestorescan_plan(PlannerInfo *root,
143 Path *best_path, List *tlist, List *scan_clauses);
144 static WorkTableScan *create_worktablescan_plan(PlannerInfo *root, Path *best_path,
145 List *tlist, List *scan_clauses);
146 static ForeignScan *create_foreignscan_plan(PlannerInfo *root, ForeignPath *best_path,
147 List *tlist, List *scan_clauses);
148 static CustomScan *create_customscan_plan(PlannerInfo *root,
149 CustomPath *best_path,
150 List *tlist, List *scan_clauses);
151 static NestLoop *create_nestloop_plan(PlannerInfo *root, NestPath *best_path);
152 static MergeJoin *create_mergejoin_plan(PlannerInfo *root, MergePath *best_path);
153 static HashJoin *create_hashjoin_plan(PlannerInfo *root, HashPath *best_path);
154 static Node *replace_nestloop_params(PlannerInfo *root, Node *expr);
155 static Node *replace_nestloop_params_mutator(Node *node, PlannerInfo *root);
156 static List *fix_indexqual_references(PlannerInfo *root, IndexPath *index_path);
157 static List *fix_indexorderby_references(PlannerInfo *root, IndexPath *index_path);
158 static Node *fix_indexqual_operand(Node *node, IndexOptInfo *index, int indexcol);
159 static List *get_switched_clauses(List *clauses, Relids outerrelids);
160 static List *order_qual_clauses(PlannerInfo *root, List *clauses);
161 static void copy_generic_path_info(Plan *dest, Path *src);
162 static void copy_plan_costsize(Plan *dest, Plan *src);
163 static void label_sort_with_costsize(PlannerInfo *root, Sort *plan,
164 double limit_tuples);
165 static SeqScan *make_seqscan(List *qptlist, List *qpqual, Index scanrelid);
166 static SampleScan *make_samplescan(List *qptlist, List *qpqual, Index scanrelid,
167 TableSampleClause *tsc);
168 static IndexScan *make_indexscan(List *qptlist, List *qpqual, Index scanrelid,
169 Oid indexid, List *indexqual, List *indexqualorig,
170 List *indexorderby, List *indexorderbyorig,
171 List *indexorderbyops,
172 ScanDirection indexscandir);
173 static IndexOnlyScan *make_indexonlyscan(List *qptlist, List *qpqual,
174 Index scanrelid, Oid indexid,
175 List *indexqual, List *indexorderby,
176 List *indextlist,
177 ScanDirection indexscandir);
178 static BitmapIndexScan *make_bitmap_indexscan(Index scanrelid, Oid indexid,
179 List *indexqual,
180 List *indexqualorig);
181 static BitmapHeapScan *make_bitmap_heapscan(List *qptlist,
182 List *qpqual,
183 Plan *lefttree,
184 List *bitmapqualorig,
185 Index scanrelid);
186 static TidScan *make_tidscan(List *qptlist, List *qpqual, Index scanrelid,
187 List *tidquals);
188 static SubqueryScan *make_subqueryscan(List *qptlist,
189 List *qpqual,
190 Index scanrelid,
191 Plan *subplan);
192 static FunctionScan *make_functionscan(List *qptlist, List *qpqual,
193 Index scanrelid, List *functions, bool funcordinality);
194 static ValuesScan *make_valuesscan(List *qptlist, List *qpqual,
195 Index scanrelid, List *values_lists);
196 static TableFuncScan *make_tablefuncscan(List *qptlist, List *qpqual,
197 Index scanrelid, TableFunc *tablefunc);
198 static CteScan *make_ctescan(List *qptlist, List *qpqual,
199 Index scanrelid, int ctePlanId, int cteParam);
200 static NamedTuplestoreScan *make_namedtuplestorescan(List *qptlist, List *qpqual,
201 Index scanrelid, char *enrname);
202 static WorkTableScan *make_worktablescan(List *qptlist, List *qpqual,
203 Index scanrelid, int wtParam);
204 static Append *make_append(List *appendplans, List *tlist, List *partitioned_rels);
205 static RecursiveUnion *make_recursive_union(List *tlist,
206 Plan *lefttree,
207 Plan *righttree,
208 int wtParam,
209 List *distinctList,
210 long numGroups);
211 static BitmapAnd *make_bitmap_and(List *bitmapplans);
212 static BitmapOr *make_bitmap_or(List *bitmapplans);
213 static NestLoop *make_nestloop(List *tlist,
214 List *joinclauses, List *otherclauses, List *nestParams,
215 Plan *lefttree, Plan *righttree,
216 JoinType jointype, bool inner_unique);
217 static HashJoin *make_hashjoin(List *tlist,
218 List *joinclauses, List *otherclauses,
219 List *hashclauses,
220 Plan *lefttree, Plan *righttree,
221 JoinType jointype, bool inner_unique);
222 static Hash *make_hash(Plan *lefttree,
223 Oid skewTable,
224 AttrNumber skewColumn,
225 bool skewInherit);
226 static MergeJoin *make_mergejoin(List *tlist,
227 List *joinclauses, List *otherclauses,
228 List *mergeclauses,
229 Oid *mergefamilies,
230 Oid *mergecollations,
231 int *mergestrategies,
232 bool *mergenullsfirst,
233 Plan *lefttree, Plan *righttree,
234 JoinType jointype, bool inner_unique,
235 bool skip_mark_restore);
236 static Sort *make_sort(Plan *lefttree, int numCols,
237 AttrNumber *sortColIdx, Oid *sortOperators,
238 Oid *collations, bool *nullsFirst);
239 static Plan *prepare_sort_from_pathkeys(Plan *lefttree, List *pathkeys,
240 Relids relids,
241 const AttrNumber *reqColIdx,
242 bool adjust_tlist_in_place,
243 int *p_numsortkeys,
244 AttrNumber **p_sortColIdx,
245 Oid **p_sortOperators,
246 Oid **p_collations,
247 bool **p_nullsFirst);
248 static EquivalenceMember *find_ec_member_for_tle(EquivalenceClass *ec,
249 TargetEntry *tle,
250 Relids relids);
251 static Sort *make_sort_from_pathkeys(Plan *lefttree, List *pathkeys);
252 static Sort *make_sort_from_groupcols(List *groupcls,
253 AttrNumber *grpColIdx,
254 Plan *lefttree);
255 static Material *make_material(Plan *lefttree);
256 static WindowAgg *make_windowagg(List *tlist, Index winref,
257 int partNumCols, AttrNumber *partColIdx, Oid *partOperators,
258 int ordNumCols, AttrNumber *ordColIdx, Oid *ordOperators,
259 int frameOptions, Node *startOffset, Node *endOffset,
260 Plan *lefttree);
261 static Group *make_group(List *tlist, List *qual, int numGroupCols,
262 AttrNumber *grpColIdx, Oid *grpOperators,
263 Plan *lefttree);
264 static Unique *make_unique_from_sortclauses(Plan *lefttree, List *distinctList);
265 static Unique *make_unique_from_pathkeys(Plan *lefttree,
266 List *pathkeys, int numCols);
267 static Gather *make_gather(List *qptlist, List *qpqual,
268 int nworkers, int rescan_param, bool single_copy, Plan *subplan);
269 static SetOp *make_setop(SetOpCmd cmd, SetOpStrategy strategy, Plan *lefttree,
270 List *distinctList, AttrNumber flagColIdx, int firstFlag,
271 long numGroups);
272 static LockRows *make_lockrows(Plan *lefttree, List *rowMarks, int epqParam);
273 static Result *make_result(List *tlist, Node *resconstantqual, Plan *subplan);
274 static ProjectSet *make_project_set(List *tlist, Plan *subplan);
275 static ModifyTable *make_modifytable(PlannerInfo *root,
276 CmdType operation, bool canSetTag,
277 Index nominalRelation, List *partitioned_rels,
278 List *resultRelations, List *subplans,
279 List *withCheckOptionLists, List *returningLists,
280 List *rowMarks, OnConflictExpr *onconflict, int epqParam);
281 static GatherMerge *create_gather_merge_plan(PlannerInfo *root,
282 GatherMergePath *best_path);
283
284
285 /*
286 * create_plan
287 * Creates the access plan for a query by recursively processing the
288 * desired tree of pathnodes, starting at the node 'best_path'. For
289 * every pathnode found, we create a corresponding plan node containing
290 * appropriate id, target list, and qualification information.
291 *
292 * The tlists and quals in the plan tree are still in planner format,
293 * ie, Vars still correspond to the parser's numbering. This will be
294 * fixed later by setrefs.c.
295 *
296 * best_path is the best access path
297 *
298 * Returns a Plan tree.
299 */
300 Plan *
create_plan(PlannerInfo * root,Path * best_path)301 create_plan(PlannerInfo *root, Path *best_path)
302 {
303 Plan *plan;
304
305 /* plan_params should not be in use in current query level */
306 Assert(root->plan_params == NIL);
307
308 /* Initialize this module's workspace in PlannerInfo */
309 root->curOuterRels = NULL;
310 root->curOuterParams = NIL;
311
312 /* Recursively process the path tree, demanding the correct tlist result */
313 plan = create_plan_recurse(root, best_path, CP_EXACT_TLIST);
314
315 /*
316 * Make sure the topmost plan node's targetlist exposes the original
317 * column names and other decorative info. Targetlists generated within
318 * the planner don't bother with that stuff, but we must have it on the
319 * top-level tlist seen at execution time. However, ModifyTable plan
320 * nodes don't have a tlist matching the querytree targetlist.
321 */
322 if (!IsA(plan, ModifyTable))
323 apply_tlist_labeling(plan->targetlist, root->processed_tlist);
324
325 /*
326 * Attach any initPlans created in this query level to the topmost plan
327 * node. (In principle the initplans could go in any plan node at or
328 * above where they're referenced, but there seems no reason to put them
329 * any lower than the topmost node for the query level. Also, see
330 * comments for SS_finalize_plan before you try to change this.)
331 */
332 SS_attach_initplans(root, plan);
333
334 /* Check we successfully assigned all NestLoopParams to plan nodes */
335 if (root->curOuterParams != NIL)
336 elog(ERROR, "failed to assign all NestLoopParams to plan nodes");
337
338 /*
339 * Reset plan_params to ensure param IDs used for nestloop params are not
340 * re-used later
341 */
342 root->plan_params = NIL;
343
344 return plan;
345 }
346
347 /*
348 * create_plan_recurse
349 * Recursive guts of create_plan().
350 */
351 static Plan *
create_plan_recurse(PlannerInfo * root,Path * best_path,int flags)352 create_plan_recurse(PlannerInfo *root, Path *best_path, int flags)
353 {
354 Plan *plan;
355
356 /* Guard against stack overflow due to overly complex plans */
357 check_stack_depth();
358
359 switch (best_path->pathtype)
360 {
361 case T_SeqScan:
362 case T_SampleScan:
363 case T_IndexScan:
364 case T_IndexOnlyScan:
365 case T_BitmapHeapScan:
366 case T_TidScan:
367 case T_SubqueryScan:
368 case T_FunctionScan:
369 case T_TableFuncScan:
370 case T_ValuesScan:
371 case T_CteScan:
372 case T_WorkTableScan:
373 case T_NamedTuplestoreScan:
374 case T_ForeignScan:
375 case T_CustomScan:
376 plan = create_scan_plan(root, best_path, flags);
377 break;
378 case T_HashJoin:
379 case T_MergeJoin:
380 case T_NestLoop:
381 plan = create_join_plan(root,
382 (JoinPath *) best_path);
383 break;
384 case T_Append:
385 plan = create_append_plan(root,
386 (AppendPath *) best_path);
387 break;
388 case T_MergeAppend:
389 plan = create_merge_append_plan(root,
390 (MergeAppendPath *) best_path,
391 flags);
392 break;
393 case T_Result:
394 if (IsA(best_path, ProjectionPath))
395 {
396 plan = create_projection_plan(root,
397 (ProjectionPath *) best_path);
398 }
399 else if (IsA(best_path, MinMaxAggPath))
400 {
401 plan = (Plan *) create_minmaxagg_plan(root,
402 (MinMaxAggPath *) best_path);
403 }
404 else
405 {
406 Assert(IsA(best_path, ResultPath));
407 plan = (Plan *) create_result_plan(root,
408 (ResultPath *) best_path);
409 }
410 break;
411 case T_ProjectSet:
412 plan = (Plan *) create_project_set_plan(root,
413 (ProjectSetPath *) best_path);
414 break;
415 case T_Material:
416 plan = (Plan *) create_material_plan(root,
417 (MaterialPath *) best_path,
418 flags);
419 break;
420 case T_Unique:
421 if (IsA(best_path, UpperUniquePath))
422 {
423 plan = (Plan *) create_upper_unique_plan(root,
424 (UpperUniquePath *) best_path,
425 flags);
426 }
427 else
428 {
429 Assert(IsA(best_path, UniquePath));
430 plan = create_unique_plan(root,
431 (UniquePath *) best_path,
432 flags);
433 }
434 break;
435 case T_Gather:
436 plan = (Plan *) create_gather_plan(root,
437 (GatherPath *) best_path);
438 break;
439 case T_Sort:
440 plan = (Plan *) create_sort_plan(root,
441 (SortPath *) best_path,
442 flags);
443 break;
444 case T_Group:
445 plan = (Plan *) create_group_plan(root,
446 (GroupPath *) best_path);
447 break;
448 case T_Agg:
449 if (IsA(best_path, GroupingSetsPath))
450 plan = create_groupingsets_plan(root,
451 (GroupingSetsPath *) best_path);
452 else
453 {
454 Assert(IsA(best_path, AggPath));
455 plan = (Plan *) create_agg_plan(root,
456 (AggPath *) best_path);
457 }
458 break;
459 case T_WindowAgg:
460 plan = (Plan *) create_windowagg_plan(root,
461 (WindowAggPath *) best_path);
462 break;
463 case T_SetOp:
464 plan = (Plan *) create_setop_plan(root,
465 (SetOpPath *) best_path,
466 flags);
467 break;
468 case T_RecursiveUnion:
469 plan = (Plan *) create_recursiveunion_plan(root,
470 (RecursiveUnionPath *) best_path);
471 break;
472 case T_LockRows:
473 plan = (Plan *) create_lockrows_plan(root,
474 (LockRowsPath *) best_path,
475 flags);
476 break;
477 case T_ModifyTable:
478 plan = (Plan *) create_modifytable_plan(root,
479 (ModifyTablePath *) best_path);
480 break;
481 case T_Limit:
482 plan = (Plan *) create_limit_plan(root,
483 (LimitPath *) best_path,
484 flags);
485 break;
486 case T_GatherMerge:
487 plan = (Plan *) create_gather_merge_plan(root,
488 (GatherMergePath *) best_path);
489 break;
490 default:
491 elog(ERROR, "unrecognized node type: %d",
492 (int) best_path->pathtype);
493 plan = NULL; /* keep compiler quiet */
494 break;
495 }
496
497 return plan;
498 }
499
500 /*
501 * create_scan_plan
502 * Create a scan plan for the parent relation of 'best_path'.
503 */
504 static Plan *
create_scan_plan(PlannerInfo * root,Path * best_path,int flags)505 create_scan_plan(PlannerInfo *root, Path *best_path, int flags)
506 {
507 RelOptInfo *rel = best_path->parent;
508 List *scan_clauses;
509 List *gating_clauses;
510 List *tlist;
511 Plan *plan;
512
513 /*
514 * Extract the relevant restriction clauses from the parent relation. The
515 * executor must apply all these restrictions during the scan, except for
516 * pseudoconstants which we'll take care of below.
517 *
518 * If this is a plain indexscan or index-only scan, we need not consider
519 * restriction clauses that are implied by the index's predicate, so use
520 * indrestrictinfo not baserestrictinfo. Note that we can't do that for
521 * bitmap indexscans, since there's not necessarily a single index
522 * involved; but it doesn't matter since create_bitmap_scan_plan() will be
523 * able to get rid of such clauses anyway via predicate proof.
524 */
525 switch (best_path->pathtype)
526 {
527 case T_IndexScan:
528 case T_IndexOnlyScan:
529 scan_clauses = castNode(IndexPath, best_path)->indexinfo->indrestrictinfo;
530 break;
531 default:
532 scan_clauses = rel->baserestrictinfo;
533 break;
534 }
535
536 /*
537 * If this is a parameterized scan, we also need to enforce all the join
538 * clauses available from the outer relation(s).
539 *
540 * For paranoia's sake, don't modify the stored baserestrictinfo list.
541 */
542 if (best_path->param_info)
543 scan_clauses = list_concat(list_copy(scan_clauses),
544 best_path->param_info->ppi_clauses);
545
546 /*
547 * Detect whether we have any pseudoconstant quals to deal with. Then, if
548 * we'll need a gating Result node, it will be able to project, so there
549 * are no requirements on the child's tlist.
550 */
551 gating_clauses = get_gating_quals(root, scan_clauses);
552 if (gating_clauses)
553 flags = 0;
554
555 /*
556 * For table scans, rather than using the relation targetlist (which is
557 * only those Vars actually needed by the query), we prefer to generate a
558 * tlist containing all Vars in order. This will allow the executor to
559 * optimize away projection of the table tuples, if possible.
560 */
561 if (use_physical_tlist(root, best_path, flags))
562 {
563 if (best_path->pathtype == T_IndexOnlyScan)
564 {
565 /* For index-only scan, the preferred tlist is the index's */
566 tlist = copyObject(((IndexPath *) best_path)->indexinfo->indextlist);
567
568 /*
569 * Transfer sortgroupref data to the replacement tlist, if
570 * requested (use_physical_tlist checked that this will work).
571 */
572 if (flags & CP_LABEL_TLIST)
573 apply_pathtarget_labeling_to_tlist(tlist, best_path->pathtarget);
574 }
575 else
576 {
577 tlist = build_physical_tlist(root, rel);
578 if (tlist == NIL)
579 {
580 /* Failed because of dropped cols, so use regular method */
581 tlist = build_path_tlist(root, best_path);
582 }
583 else
584 {
585 /* As above, transfer sortgroupref data to replacement tlist */
586 if (flags & CP_LABEL_TLIST)
587 apply_pathtarget_labeling_to_tlist(tlist, best_path->pathtarget);
588 }
589 }
590 }
591 else
592 {
593 tlist = build_path_tlist(root, best_path);
594 }
595
596 switch (best_path->pathtype)
597 {
598 case T_SeqScan:
599 plan = (Plan *) create_seqscan_plan(root,
600 best_path,
601 tlist,
602 scan_clauses);
603 break;
604
605 case T_SampleScan:
606 plan = (Plan *) create_samplescan_plan(root,
607 best_path,
608 tlist,
609 scan_clauses);
610 break;
611
612 case T_IndexScan:
613 plan = (Plan *) create_indexscan_plan(root,
614 (IndexPath *) best_path,
615 tlist,
616 scan_clauses,
617 false);
618 break;
619
620 case T_IndexOnlyScan:
621 plan = (Plan *) create_indexscan_plan(root,
622 (IndexPath *) best_path,
623 tlist,
624 scan_clauses,
625 true);
626 break;
627
628 case T_BitmapHeapScan:
629 plan = (Plan *) create_bitmap_scan_plan(root,
630 (BitmapHeapPath *) best_path,
631 tlist,
632 scan_clauses);
633 break;
634
635 case T_TidScan:
636 plan = (Plan *) create_tidscan_plan(root,
637 (TidPath *) best_path,
638 tlist,
639 scan_clauses);
640 break;
641
642 case T_SubqueryScan:
643 plan = (Plan *) create_subqueryscan_plan(root,
644 (SubqueryScanPath *) best_path,
645 tlist,
646 scan_clauses);
647 break;
648
649 case T_FunctionScan:
650 plan = (Plan *) create_functionscan_plan(root,
651 best_path,
652 tlist,
653 scan_clauses);
654 break;
655
656 case T_TableFuncScan:
657 plan = (Plan *) create_tablefuncscan_plan(root,
658 best_path,
659 tlist,
660 scan_clauses);
661 break;
662
663 case T_ValuesScan:
664 plan = (Plan *) create_valuesscan_plan(root,
665 best_path,
666 tlist,
667 scan_clauses);
668 break;
669
670 case T_CteScan:
671 plan = (Plan *) create_ctescan_plan(root,
672 best_path,
673 tlist,
674 scan_clauses);
675 break;
676
677 case T_NamedTuplestoreScan:
678 plan = (Plan *) create_namedtuplestorescan_plan(root,
679 best_path,
680 tlist,
681 scan_clauses);
682 break;
683
684 case T_WorkTableScan:
685 plan = (Plan *) create_worktablescan_plan(root,
686 best_path,
687 tlist,
688 scan_clauses);
689 break;
690
691 case T_ForeignScan:
692 plan = (Plan *) create_foreignscan_plan(root,
693 (ForeignPath *) best_path,
694 tlist,
695 scan_clauses);
696 break;
697
698 case T_CustomScan:
699 plan = (Plan *) create_customscan_plan(root,
700 (CustomPath *) best_path,
701 tlist,
702 scan_clauses);
703 break;
704
705 default:
706 elog(ERROR, "unrecognized node type: %d",
707 (int) best_path->pathtype);
708 plan = NULL; /* keep compiler quiet */
709 break;
710 }
711
712 /*
713 * If there are any pseudoconstant clauses attached to this node, insert a
714 * gating Result node that evaluates the pseudoconstants as one-time
715 * quals.
716 */
717 if (gating_clauses)
718 plan = create_gating_plan(root, best_path, plan, gating_clauses);
719
720 return plan;
721 }
722
723 /*
724 * Build a target list (ie, a list of TargetEntry) for the Path's output.
725 *
726 * This is almost just make_tlist_from_pathtarget(), but we also have to
727 * deal with replacing nestloop params.
728 */
729 static List *
build_path_tlist(PlannerInfo * root,Path * path)730 build_path_tlist(PlannerInfo *root, Path *path)
731 {
732 List *tlist = NIL;
733 Index *sortgrouprefs = path->pathtarget->sortgrouprefs;
734 int resno = 1;
735 ListCell *v;
736
737 foreach(v, path->pathtarget->exprs)
738 {
739 Node *node = (Node *) lfirst(v);
740 TargetEntry *tle;
741
742 /*
743 * If it's a parameterized path, there might be lateral references in
744 * the tlist, which need to be replaced with Params. There's no need
745 * to remake the TargetEntry nodes, so apply this to each list item
746 * separately.
747 */
748 if (path->param_info)
749 node = replace_nestloop_params(root, node);
750
751 tle = makeTargetEntry((Expr *) node,
752 resno,
753 NULL,
754 false);
755 if (sortgrouprefs)
756 tle->ressortgroupref = sortgrouprefs[resno - 1];
757
758 tlist = lappend(tlist, tle);
759 resno++;
760 }
761 return tlist;
762 }
763
764 /*
765 * use_physical_tlist
766 * Decide whether to use a tlist matching relation structure,
767 * rather than only those Vars actually referenced.
768 */
769 static bool
use_physical_tlist(PlannerInfo * root,Path * path,int flags)770 use_physical_tlist(PlannerInfo *root, Path *path, int flags)
771 {
772 RelOptInfo *rel = path->parent;
773 int i;
774 ListCell *lc;
775
776 /*
777 * Forget it if either exact tlist or small tlist is demanded.
778 */
779 if (flags & (CP_EXACT_TLIST | CP_SMALL_TLIST))
780 return false;
781
782 /*
783 * We can do this for real relation scans, subquery scans, function scans,
784 * tablefunc scans, values scans, and CTE scans (but not for, eg, joins).
785 */
786 if (rel->rtekind != RTE_RELATION &&
787 rel->rtekind != RTE_SUBQUERY &&
788 rel->rtekind != RTE_FUNCTION &&
789 rel->rtekind != RTE_TABLEFUNC &&
790 rel->rtekind != RTE_VALUES &&
791 rel->rtekind != RTE_CTE)
792 return false;
793
794 /*
795 * Can't do it with inheritance cases either (mainly because Append
796 * doesn't project; this test may be unnecessary now that
797 * create_append_plan instructs its children to return an exact tlist).
798 */
799 if (rel->reloptkind != RELOPT_BASEREL)
800 return false;
801
802 /*
803 * Also, don't do it to a CustomPath; the premise that we're extracting
804 * columns from a simple physical tuple is unlikely to hold for those.
805 * (When it does make sense, the custom path creator can set up the path's
806 * pathtarget that way.)
807 */
808 if (IsA(path, CustomPath))
809 return false;
810
811 /*
812 * Can't do it if any system columns or whole-row Vars are requested.
813 * (This could possibly be fixed but would take some fragile assumptions
814 * in setrefs.c, I think.)
815 */
816 for (i = rel->min_attr; i <= 0; i++)
817 {
818 if (!bms_is_empty(rel->attr_needed[i - rel->min_attr]))
819 return false;
820 }
821
822 /*
823 * Can't do it if the rel is required to emit any placeholder expressions,
824 * either.
825 */
826 foreach(lc, root->placeholder_list)
827 {
828 PlaceHolderInfo *phinfo = (PlaceHolderInfo *) lfirst(lc);
829
830 if (bms_nonempty_difference(phinfo->ph_needed, rel->relids) &&
831 bms_is_subset(phinfo->ph_eval_at, rel->relids))
832 return false;
833 }
834
835 /*
836 * Also, can't do it if CP_LABEL_TLIST is specified and path is requested
837 * to emit any sort/group columns that are not simple Vars. (If they are
838 * simple Vars, they should appear in the physical tlist, and
839 * apply_pathtarget_labeling_to_tlist will take care of getting them
840 * labeled again.) We also have to check that no two sort/group columns
841 * are the same Var, else that element of the physical tlist would need
842 * conflicting ressortgroupref labels.
843 */
844 if ((flags & CP_LABEL_TLIST) && path->pathtarget->sortgrouprefs)
845 {
846 Bitmapset *sortgroupatts = NULL;
847
848 i = 0;
849 foreach(lc, path->pathtarget->exprs)
850 {
851 Expr *expr = (Expr *) lfirst(lc);
852
853 if (path->pathtarget->sortgrouprefs[i])
854 {
855 if (expr && IsA(expr, Var))
856 {
857 int attno = ((Var *) expr)->varattno;
858
859 attno -= FirstLowInvalidHeapAttributeNumber;
860 if (bms_is_member(attno, sortgroupatts))
861 return false;
862 sortgroupatts = bms_add_member(sortgroupatts, attno);
863 }
864 else
865 return false;
866 }
867 i++;
868 }
869 }
870
871 return true;
872 }
873
874 /*
875 * get_gating_quals
876 * See if there are pseudoconstant quals in a node's quals list
877 *
878 * If the node's quals list includes any pseudoconstant quals,
879 * return just those quals.
880 */
881 static List *
get_gating_quals(PlannerInfo * root,List * quals)882 get_gating_quals(PlannerInfo *root, List *quals)
883 {
884 /* No need to look if we know there are no pseudoconstants */
885 if (!root->hasPseudoConstantQuals)
886 return NIL;
887
888 /* Sort into desirable execution order while still in RestrictInfo form */
889 quals = order_qual_clauses(root, quals);
890
891 /* Pull out any pseudoconstant quals from the RestrictInfo list */
892 return extract_actual_clauses(quals, true);
893 }
894
895 /*
896 * create_gating_plan
897 * Deal with pseudoconstant qual clauses
898 *
899 * Add a gating Result node atop the already-built plan.
900 */
901 static Plan *
create_gating_plan(PlannerInfo * root,Path * path,Plan * plan,List * gating_quals)902 create_gating_plan(PlannerInfo *root, Path *path, Plan *plan,
903 List *gating_quals)
904 {
905 Plan *gplan;
906
907 Assert(gating_quals);
908
909 /*
910 * Since we need a Result node anyway, always return the path's requested
911 * tlist; that's never a wrong choice, even if the parent node didn't ask
912 * for CP_EXACT_TLIST.
913 */
914 gplan = (Plan *) make_result(build_path_tlist(root, path),
915 (Node *) gating_quals,
916 plan);
917
918 /*
919 * Notice that we don't change cost or size estimates when doing gating.
920 * The costs of qual eval were already included in the subplan's cost.
921 * Leaving the size alone amounts to assuming that the gating qual will
922 * succeed, which is the conservative estimate for planning upper queries.
923 * We certainly don't want to assume the output size is zero (unless the
924 * gating qual is actually constant FALSE, and that case is dealt with in
925 * clausesel.c). Interpolating between the two cases is silly, because it
926 * doesn't reflect what will really happen at runtime, and besides which
927 * in most cases we have only a very bad idea of the probability of the
928 * gating qual being true.
929 */
930 copy_plan_costsize(gplan, plan);
931
932 /* Gating quals could be unsafe, so better use the Path's safety flag */
933 gplan->parallel_safe = path->parallel_safe;
934
935 return gplan;
936 }
937
938 /*
939 * create_join_plan
940 * Create a join plan for 'best_path' and (recursively) plans for its
941 * inner and outer paths.
942 */
943 static Plan *
create_join_plan(PlannerInfo * root,JoinPath * best_path)944 create_join_plan(PlannerInfo *root, JoinPath *best_path)
945 {
946 Plan *plan;
947 List *gating_clauses;
948
949 switch (best_path->path.pathtype)
950 {
951 case T_MergeJoin:
952 plan = (Plan *) create_mergejoin_plan(root,
953 (MergePath *) best_path);
954 break;
955 case T_HashJoin:
956 plan = (Plan *) create_hashjoin_plan(root,
957 (HashPath *) best_path);
958 break;
959 case T_NestLoop:
960 plan = (Plan *) create_nestloop_plan(root,
961 (NestPath *) best_path);
962 break;
963 default:
964 elog(ERROR, "unrecognized node type: %d",
965 (int) best_path->path.pathtype);
966 plan = NULL; /* keep compiler quiet */
967 break;
968 }
969
970 /*
971 * If there are any pseudoconstant clauses attached to this node, insert a
972 * gating Result node that evaluates the pseudoconstants as one-time
973 * quals.
974 */
975 gating_clauses = get_gating_quals(root, best_path->joinrestrictinfo);
976 if (gating_clauses)
977 plan = create_gating_plan(root, (Path *) best_path, plan,
978 gating_clauses);
979
980 #ifdef NOT_USED
981
982 /*
983 * * Expensive function pullups may have pulled local predicates * into
984 * this path node. Put them in the qpqual of the plan node. * JMH,
985 * 6/15/92
986 */
987 if (get_loc_restrictinfo(best_path) != NIL)
988 set_qpqual((Plan) plan,
989 list_concat(get_qpqual((Plan) plan),
990 get_actual_clauses(get_loc_restrictinfo(best_path))));
991 #endif
992
993 return plan;
994 }
995
996 /*
997 * create_append_plan
998 * Create an Append plan for 'best_path' and (recursively) plans
999 * for its subpaths.
1000 *
1001 * Returns a Plan node.
1002 */
1003 static Plan *
create_append_plan(PlannerInfo * root,AppendPath * best_path)1004 create_append_plan(PlannerInfo *root, AppendPath *best_path)
1005 {
1006 Append *plan;
1007 List *tlist = build_path_tlist(root, &best_path->path);
1008 List *subplans = NIL;
1009 ListCell *subpaths;
1010
1011 /*
1012 * The subpaths list could be empty, if every child was proven empty by
1013 * constraint exclusion. In that case generate a dummy plan that returns
1014 * no rows.
1015 *
1016 * Note that an AppendPath with no members is also generated in certain
1017 * cases where there was no appending construct at all, but we know the
1018 * relation is empty (see set_dummy_rel_pathlist and mark_dummy_rel).
1019 */
1020 if (best_path->subpaths == NIL)
1021 {
1022 /* Generate a Result plan with constant-FALSE gating qual */
1023 Plan *plan;
1024
1025 plan = (Plan *) make_result(tlist,
1026 (Node *) list_make1(makeBoolConst(false,
1027 false)),
1028 NULL);
1029
1030 copy_generic_path_info(plan, (Path *) best_path);
1031
1032 return plan;
1033 }
1034
1035 /* Build the plan for each child */
1036 foreach(subpaths, best_path->subpaths)
1037 {
1038 Path *subpath = (Path *) lfirst(subpaths);
1039 Plan *subplan;
1040
1041 /* Must insist that all children return the same tlist */
1042 subplan = create_plan_recurse(root, subpath, CP_EXACT_TLIST);
1043
1044 subplans = lappend(subplans, subplan);
1045 }
1046
1047 /*
1048 * XXX ideally, if there's just one child, we'd not bother to generate an
1049 * Append node but just return the single child. At the moment this does
1050 * not work because the varno of the child scan plan won't match the
1051 * parent-rel Vars it'll be asked to emit.
1052 */
1053
1054 plan = make_append(subplans, tlist, best_path->partitioned_rels);
1055
1056 copy_generic_path_info(&plan->plan, (Path *) best_path);
1057
1058 return (Plan *) plan;
1059 }
1060
1061 /*
1062 * create_merge_append_plan
1063 * Create a MergeAppend plan for 'best_path' and (recursively) plans
1064 * for its subpaths.
1065 *
1066 * Returns a Plan node.
1067 */
1068 static Plan *
create_merge_append_plan(PlannerInfo * root,MergeAppendPath * best_path,int flags)1069 create_merge_append_plan(PlannerInfo *root, MergeAppendPath *best_path,
1070 int flags)
1071 {
1072 MergeAppend *node = makeNode(MergeAppend);
1073 Plan *plan = &node->plan;
1074 List *tlist = build_path_tlist(root, &best_path->path);
1075 int orig_tlist_length = list_length(tlist);
1076 bool tlist_was_changed;
1077 List *pathkeys = best_path->path.pathkeys;
1078 List *subplans = NIL;
1079 ListCell *subpaths;
1080
1081 /*
1082 * We don't have the actual creation of the MergeAppend node split out
1083 * into a separate make_xxx function. This is because we want to run
1084 * prepare_sort_from_pathkeys on it before we do so on the individual
1085 * child plans, to make cross-checking the sort info easier.
1086 */
1087 copy_generic_path_info(plan, (Path *) best_path);
1088 plan->targetlist = tlist;
1089 plan->qual = NIL;
1090 plan->lefttree = NULL;
1091 plan->righttree = NULL;
1092
1093 /*
1094 * Compute sort column info, and adjust MergeAppend's tlist as needed.
1095 * Because we pass adjust_tlist_in_place = true, we may ignore the
1096 * function result; it must be the same plan node. However, we then need
1097 * to detect whether any tlist entries were added.
1098 */
1099 (void) prepare_sort_from_pathkeys(plan, pathkeys,
1100 best_path->path.parent->relids,
1101 NULL,
1102 true,
1103 &node->numCols,
1104 &node->sortColIdx,
1105 &node->sortOperators,
1106 &node->collations,
1107 &node->nullsFirst);
1108 tlist_was_changed = (orig_tlist_length != list_length(plan->targetlist));
1109
1110 /*
1111 * Now prepare the child plans. We must apply prepare_sort_from_pathkeys
1112 * even to subplans that don't need an explicit sort, to make sure they
1113 * are returning the same sort key columns the MergeAppend expects.
1114 */
1115 foreach(subpaths, best_path->subpaths)
1116 {
1117 Path *subpath = (Path *) lfirst(subpaths);
1118 Plan *subplan;
1119 int numsortkeys;
1120 AttrNumber *sortColIdx;
1121 Oid *sortOperators;
1122 Oid *collations;
1123 bool *nullsFirst;
1124
1125 /* Build the child plan */
1126 /* Must insist that all children return the same tlist */
1127 subplan = create_plan_recurse(root, subpath, CP_EXACT_TLIST);
1128
1129 /* Compute sort column info, and adjust subplan's tlist as needed */
1130 subplan = prepare_sort_from_pathkeys(subplan, pathkeys,
1131 subpath->parent->relids,
1132 node->sortColIdx,
1133 false,
1134 &numsortkeys,
1135 &sortColIdx,
1136 &sortOperators,
1137 &collations,
1138 &nullsFirst);
1139
1140 /*
1141 * Check that we got the same sort key information. We just Assert
1142 * that the sortops match, since those depend only on the pathkeys;
1143 * but it seems like a good idea to check the sort column numbers
1144 * explicitly, to ensure the tlists really do match up.
1145 */
1146 Assert(numsortkeys == node->numCols);
1147 if (memcmp(sortColIdx, node->sortColIdx,
1148 numsortkeys * sizeof(AttrNumber)) != 0)
1149 elog(ERROR, "MergeAppend child's targetlist doesn't match MergeAppend");
1150 Assert(memcmp(sortOperators, node->sortOperators,
1151 numsortkeys * sizeof(Oid)) == 0);
1152 Assert(memcmp(collations, node->collations,
1153 numsortkeys * sizeof(Oid)) == 0);
1154 Assert(memcmp(nullsFirst, node->nullsFirst,
1155 numsortkeys * sizeof(bool)) == 0);
1156
1157 /* Now, insert a Sort node if subplan isn't sufficiently ordered */
1158 if (!pathkeys_contained_in(pathkeys, subpath->pathkeys))
1159 {
1160 Sort *sort = make_sort(subplan, numsortkeys,
1161 sortColIdx, sortOperators,
1162 collations, nullsFirst);
1163
1164 label_sort_with_costsize(root, sort, best_path->limit_tuples);
1165 subplan = (Plan *) sort;
1166 }
1167
1168 subplans = lappend(subplans, subplan);
1169 }
1170
1171 node->partitioned_rels = best_path->partitioned_rels;
1172 node->mergeplans = subplans;
1173
1174 /*
1175 * If prepare_sort_from_pathkeys added sort columns, but we were told to
1176 * produce either the exact tlist or a narrow tlist, we should get rid of
1177 * the sort columns again. We must inject a projection node to do so.
1178 */
1179 if (tlist_was_changed && (flags & (CP_EXACT_TLIST | CP_SMALL_TLIST)))
1180 {
1181 tlist = list_truncate(list_copy(plan->targetlist), orig_tlist_length);
1182 return inject_projection_plan(plan, tlist, plan->parallel_safe);
1183 }
1184 else
1185 return plan;
1186 }
1187
1188 /*
1189 * create_result_plan
1190 * Create a Result plan for 'best_path'.
1191 * This is only used for degenerate cases, such as a query with an empty
1192 * jointree.
1193 *
1194 * Returns a Plan node.
1195 */
1196 static Result *
create_result_plan(PlannerInfo * root,ResultPath * best_path)1197 create_result_plan(PlannerInfo *root, ResultPath *best_path)
1198 {
1199 Result *plan;
1200 List *tlist;
1201 List *quals;
1202
1203 tlist = build_path_tlist(root, &best_path->path);
1204
1205 /* best_path->quals is just bare clauses */
1206 quals = order_qual_clauses(root, best_path->quals);
1207
1208 plan = make_result(tlist, (Node *) quals, NULL);
1209
1210 copy_generic_path_info(&plan->plan, (Path *) best_path);
1211
1212 return plan;
1213 }
1214
1215 /*
1216 * create_project_set_plan
1217 * Create a ProjectSet plan for 'best_path'.
1218 *
1219 * Returns a Plan node.
1220 */
1221 static ProjectSet *
create_project_set_plan(PlannerInfo * root,ProjectSetPath * best_path)1222 create_project_set_plan(PlannerInfo *root, ProjectSetPath *best_path)
1223 {
1224 ProjectSet *plan;
1225 Plan *subplan;
1226 List *tlist;
1227
1228 /* Since we intend to project, we don't need to constrain child tlist */
1229 subplan = create_plan_recurse(root, best_path->subpath, 0);
1230
1231 tlist = build_path_tlist(root, &best_path->path);
1232
1233 plan = make_project_set(tlist, subplan);
1234
1235 copy_generic_path_info(&plan->plan, (Path *) best_path);
1236
1237 return plan;
1238 }
1239
1240 /*
1241 * create_material_plan
1242 * Create a Material plan for 'best_path' and (recursively) plans
1243 * for its subpaths.
1244 *
1245 * Returns a Plan node.
1246 */
1247 static Material *
create_material_plan(PlannerInfo * root,MaterialPath * best_path,int flags)1248 create_material_plan(PlannerInfo *root, MaterialPath *best_path, int flags)
1249 {
1250 Material *plan;
1251 Plan *subplan;
1252
1253 /*
1254 * We don't want any excess columns in the materialized tuples, so request
1255 * a smaller tlist. Otherwise, since Material doesn't project, tlist
1256 * requirements pass through.
1257 */
1258 subplan = create_plan_recurse(root, best_path->subpath,
1259 flags | CP_SMALL_TLIST);
1260
1261 plan = make_material(subplan);
1262
1263 copy_generic_path_info(&plan->plan, (Path *) best_path);
1264
1265 return plan;
1266 }
1267
1268 /*
1269 * create_unique_plan
1270 * Create a Unique plan for 'best_path' and (recursively) plans
1271 * for its subpaths.
1272 *
1273 * Returns a Plan node.
1274 */
1275 static Plan *
create_unique_plan(PlannerInfo * root,UniquePath * best_path,int flags)1276 create_unique_plan(PlannerInfo *root, UniquePath *best_path, int flags)
1277 {
1278 Plan *plan;
1279 Plan *subplan;
1280 List *in_operators;
1281 List *uniq_exprs;
1282 List *newtlist;
1283 int nextresno;
1284 bool newitems;
1285 int numGroupCols;
1286 AttrNumber *groupColIdx;
1287 int groupColPos;
1288 ListCell *l;
1289
1290 /* Unique doesn't project, so tlist requirements pass through */
1291 subplan = create_plan_recurse(root, best_path->subpath, flags);
1292
1293 /* Done if we don't need to do any actual unique-ifying */
1294 if (best_path->umethod == UNIQUE_PATH_NOOP)
1295 return subplan;
1296
1297 /*
1298 * As constructed, the subplan has a "flat" tlist containing just the Vars
1299 * needed here and at upper levels. The values we are supposed to
1300 * unique-ify may be expressions in these variables. We have to add any
1301 * such expressions to the subplan's tlist.
1302 *
1303 * The subplan may have a "physical" tlist if it is a simple scan plan. If
1304 * we're going to sort, this should be reduced to the regular tlist, so
1305 * that we don't sort more data than we need to. For hashing, the tlist
1306 * should be left as-is if we don't need to add any expressions; but if we
1307 * do have to add expressions, then a projection step will be needed at
1308 * runtime anyway, so we may as well remove unneeded items. Therefore
1309 * newtlist starts from build_path_tlist() not just a copy of the
1310 * subplan's tlist; and we don't install it into the subplan unless we are
1311 * sorting or stuff has to be added.
1312 */
1313 in_operators = best_path->in_operators;
1314 uniq_exprs = best_path->uniq_exprs;
1315
1316 /* initialize modified subplan tlist as just the "required" vars */
1317 newtlist = build_path_tlist(root, &best_path->path);
1318 nextresno = list_length(newtlist) + 1;
1319 newitems = false;
1320
1321 foreach(l, uniq_exprs)
1322 {
1323 Expr *uniqexpr = lfirst(l);
1324 TargetEntry *tle;
1325
1326 tle = tlist_member(uniqexpr, newtlist);
1327 if (!tle)
1328 {
1329 tle = makeTargetEntry((Expr *) uniqexpr,
1330 nextresno,
1331 NULL,
1332 false);
1333 newtlist = lappend(newtlist, tle);
1334 nextresno++;
1335 newitems = true;
1336 }
1337 }
1338
1339 /* Use change_plan_targetlist in case we need to insert a Result node */
1340 if (newitems || best_path->umethod == UNIQUE_PATH_SORT)
1341 subplan = change_plan_targetlist(subplan, newtlist,
1342 best_path->path.parallel_safe);
1343
1344 /*
1345 * Build control information showing which subplan output columns are to
1346 * be examined by the grouping step. Unfortunately we can't merge this
1347 * with the previous loop, since we didn't then know which version of the
1348 * subplan tlist we'd end up using.
1349 */
1350 newtlist = subplan->targetlist;
1351 numGroupCols = list_length(uniq_exprs);
1352 groupColIdx = (AttrNumber *) palloc(numGroupCols * sizeof(AttrNumber));
1353
1354 groupColPos = 0;
1355 foreach(l, uniq_exprs)
1356 {
1357 Expr *uniqexpr = lfirst(l);
1358 TargetEntry *tle;
1359
1360 tle = tlist_member(uniqexpr, newtlist);
1361 if (!tle) /* shouldn't happen */
1362 elog(ERROR, "failed to find unique expression in subplan tlist");
1363 groupColIdx[groupColPos++] = tle->resno;
1364 }
1365
1366 if (best_path->umethod == UNIQUE_PATH_HASH)
1367 {
1368 Oid *groupOperators;
1369
1370 /*
1371 * Get the hashable equality operators for the Agg node to use.
1372 * Normally these are the same as the IN clause operators, but if
1373 * those are cross-type operators then the equality operators are the
1374 * ones for the IN clause operators' RHS datatype.
1375 */
1376 groupOperators = (Oid *) palloc(numGroupCols * sizeof(Oid));
1377 groupColPos = 0;
1378 foreach(l, in_operators)
1379 {
1380 Oid in_oper = lfirst_oid(l);
1381 Oid eq_oper;
1382
1383 if (!get_compatible_hash_operators(in_oper, NULL, &eq_oper))
1384 elog(ERROR, "could not find compatible hash operator for operator %u",
1385 in_oper);
1386 groupOperators[groupColPos++] = eq_oper;
1387 }
1388
1389 /*
1390 * Since the Agg node is going to project anyway, we can give it the
1391 * minimum output tlist, without any stuff we might have added to the
1392 * subplan tlist.
1393 */
1394 plan = (Plan *) make_agg(build_path_tlist(root, &best_path->path),
1395 NIL,
1396 AGG_HASHED,
1397 AGGSPLIT_SIMPLE,
1398 numGroupCols,
1399 groupColIdx,
1400 groupOperators,
1401 NIL,
1402 NIL,
1403 best_path->path.rows,
1404 subplan);
1405 }
1406 else
1407 {
1408 List *sortList = NIL;
1409 Sort *sort;
1410
1411 /* Create an ORDER BY list to sort the input compatibly */
1412 groupColPos = 0;
1413 foreach(l, in_operators)
1414 {
1415 Oid in_oper = lfirst_oid(l);
1416 Oid sortop;
1417 Oid eqop;
1418 TargetEntry *tle;
1419 SortGroupClause *sortcl;
1420
1421 sortop = get_ordering_op_for_equality_op(in_oper, false);
1422 if (!OidIsValid(sortop)) /* shouldn't happen */
1423 elog(ERROR, "could not find ordering operator for equality operator %u",
1424 in_oper);
1425
1426 /*
1427 * The Unique node will need equality operators. Normally these
1428 * are the same as the IN clause operators, but if those are
1429 * cross-type operators then the equality operators are the ones
1430 * for the IN clause operators' RHS datatype.
1431 */
1432 eqop = get_equality_op_for_ordering_op(sortop, NULL);
1433 if (!OidIsValid(eqop)) /* shouldn't happen */
1434 elog(ERROR, "could not find equality operator for ordering operator %u",
1435 sortop);
1436
1437 tle = get_tle_by_resno(subplan->targetlist,
1438 groupColIdx[groupColPos]);
1439 Assert(tle != NULL);
1440
1441 sortcl = makeNode(SortGroupClause);
1442 sortcl->tleSortGroupRef = assignSortGroupRef(tle,
1443 subplan->targetlist);
1444 sortcl->eqop = eqop;
1445 sortcl->sortop = sortop;
1446 sortcl->nulls_first = false;
1447 sortcl->hashable = false; /* no need to make this accurate */
1448 sortList = lappend(sortList, sortcl);
1449 groupColPos++;
1450 }
1451 sort = make_sort_from_sortclauses(sortList, subplan);
1452 label_sort_with_costsize(root, sort, -1.0);
1453 plan = (Plan *) make_unique_from_sortclauses((Plan *) sort, sortList);
1454 }
1455
1456 /* Copy cost data from Path to Plan */
1457 copy_generic_path_info(plan, &best_path->path);
1458
1459 return plan;
1460 }
1461
1462 /*
1463 * create_gather_plan
1464 *
1465 * Create a Gather plan for 'best_path' and (recursively) plans
1466 * for its subpaths.
1467 */
1468 static Gather *
create_gather_plan(PlannerInfo * root,GatherPath * best_path)1469 create_gather_plan(PlannerInfo *root, GatherPath *best_path)
1470 {
1471 Gather *gather_plan;
1472 Plan *subplan;
1473 List *tlist;
1474
1475 /*
1476 * Although the Gather node can project, we prefer to push down such work
1477 * to its child node, so demand an exact tlist from the child.
1478 */
1479 subplan = create_plan_recurse(root, best_path->subpath, CP_EXACT_TLIST);
1480
1481 tlist = build_path_tlist(root, &best_path->path);
1482
1483 gather_plan = make_gather(tlist,
1484 NIL,
1485 best_path->num_workers,
1486 assign_special_exec_param(root),
1487 best_path->single_copy,
1488 subplan);
1489
1490 copy_generic_path_info(&gather_plan->plan, &best_path->path);
1491
1492 /* use parallel mode for parallel plans. */
1493 root->glob->parallelModeNeeded = true;
1494
1495 return gather_plan;
1496 }
1497
1498 /*
1499 * create_gather_merge_plan
1500 *
1501 * Create a Gather Merge plan for 'best_path' and (recursively)
1502 * plans for its subpaths.
1503 */
1504 static GatherMerge *
create_gather_merge_plan(PlannerInfo * root,GatherMergePath * best_path)1505 create_gather_merge_plan(PlannerInfo *root, GatherMergePath *best_path)
1506 {
1507 GatherMerge *gm_plan;
1508 Plan *subplan;
1509 List *pathkeys = best_path->path.pathkeys;
1510 List *tlist = build_path_tlist(root, &best_path->path);
1511
1512 /* As with Gather, it's best to project away columns in the workers. */
1513 subplan = create_plan_recurse(root, best_path->subpath, CP_EXACT_TLIST);
1514
1515 /* Create a shell for a GatherMerge plan. */
1516 gm_plan = makeNode(GatherMerge);
1517 gm_plan->plan.targetlist = tlist;
1518 gm_plan->num_workers = best_path->num_workers;
1519 copy_generic_path_info(&gm_plan->plan, &best_path->path);
1520
1521 /* Assign the rescan Param. */
1522 gm_plan->rescan_param = assign_special_exec_param(root);
1523
1524 /* Gather Merge is pointless with no pathkeys; use Gather instead. */
1525 Assert(pathkeys != NIL);
1526
1527 /* Compute sort column info, and adjust subplan's tlist as needed */
1528 subplan = prepare_sort_from_pathkeys(subplan, pathkeys,
1529 best_path->subpath->parent->relids,
1530 gm_plan->sortColIdx,
1531 false,
1532 &gm_plan->numCols,
1533 &gm_plan->sortColIdx,
1534 &gm_plan->sortOperators,
1535 &gm_plan->collations,
1536 &gm_plan->nullsFirst);
1537
1538
1539 /* Now, insert a Sort node if subplan isn't sufficiently ordered */
1540 if (!pathkeys_contained_in(pathkeys, best_path->subpath->pathkeys))
1541 subplan = (Plan *) make_sort(subplan, gm_plan->numCols,
1542 gm_plan->sortColIdx,
1543 gm_plan->sortOperators,
1544 gm_plan->collations,
1545 gm_plan->nullsFirst);
1546
1547 /* Now insert the subplan under GatherMerge. */
1548 gm_plan->plan.lefttree = subplan;
1549
1550 /* use parallel mode for parallel plans. */
1551 root->glob->parallelModeNeeded = true;
1552
1553 return gm_plan;
1554 }
1555
1556 /*
1557 * create_projection_plan
1558 *
1559 * Create a plan tree to do a projection step and (recursively) plans
1560 * for its subpaths. We may need a Result node for the projection,
1561 * but sometimes we can just let the subplan do the work.
1562 */
1563 static Plan *
create_projection_plan(PlannerInfo * root,ProjectionPath * best_path)1564 create_projection_plan(PlannerInfo *root, ProjectionPath *best_path)
1565 {
1566 Plan *plan;
1567 Plan *subplan;
1568 List *tlist;
1569
1570 /* Since we intend to project, we don't need to constrain child tlist */
1571 subplan = create_plan_recurse(root, best_path->subpath, 0);
1572
1573 tlist = build_path_tlist(root, &best_path->path);
1574
1575 /*
1576 * We might not really need a Result node here, either because the subplan
1577 * can project or because it's returning the right list of expressions
1578 * anyway. Usually create_projection_path will have detected that and set
1579 * dummypp if we don't need a Result; but its decision can't be final,
1580 * because some createplan.c routines change the tlists of their nodes.
1581 * (An example is that create_merge_append_plan might add resjunk sort
1582 * columns to a MergeAppend.) So we have to recheck here. If we do
1583 * arrive at a different answer than create_projection_path did, we'll
1584 * have made slightly wrong cost estimates; but label the plan with the
1585 * cost estimates we actually used, not "corrected" ones. (XXX this could
1586 * be cleaned up if we moved more of the sortcolumn setup logic into Path
1587 * creation, but that would add expense to creating Paths we might end up
1588 * not using.)
1589 */
1590 if (is_projection_capable_path(best_path->subpath) ||
1591 tlist_same_exprs(tlist, subplan->targetlist))
1592 {
1593 /* Don't need a separate Result, just assign tlist to subplan */
1594 plan = subplan;
1595 plan->targetlist = tlist;
1596
1597 /* Label plan with the estimated costs we actually used */
1598 plan->startup_cost = best_path->path.startup_cost;
1599 plan->total_cost = best_path->path.total_cost;
1600 plan->plan_rows = best_path->path.rows;
1601 plan->plan_width = best_path->path.pathtarget->width;
1602 plan->parallel_safe = best_path->path.parallel_safe;
1603 /* ... but don't change subplan's parallel_aware flag */
1604 }
1605 else
1606 {
1607 /* We need a Result node */
1608 plan = (Plan *) make_result(tlist, NULL, subplan);
1609
1610 copy_generic_path_info(plan, (Path *) best_path);
1611 }
1612
1613 return plan;
1614 }
1615
1616 /*
1617 * inject_projection_plan
1618 * Insert a Result node to do a projection step.
1619 *
1620 * This is used in a few places where we decide on-the-fly that we need a
1621 * projection step as part of the tree generated for some Path node.
1622 * We should try to get rid of this in favor of doing it more honestly.
1623 *
1624 * One reason it's ugly is we have to be told the right parallel_safe marking
1625 * to apply (since the tlist might be unsafe even if the child plan is safe).
1626 */
1627 static Plan *
inject_projection_plan(Plan * subplan,List * tlist,bool parallel_safe)1628 inject_projection_plan(Plan *subplan, List *tlist, bool parallel_safe)
1629 {
1630 Plan *plan;
1631
1632 plan = (Plan *) make_result(tlist, NULL, subplan);
1633
1634 /*
1635 * In principle, we should charge tlist eval cost plus cpu_per_tuple per
1636 * row for the Result node. But the former has probably been factored in
1637 * already and the latter was not accounted for during Path construction,
1638 * so being formally correct might just make the EXPLAIN output look less
1639 * consistent not more so. Hence, just copy the subplan's cost.
1640 */
1641 copy_plan_costsize(plan, subplan);
1642 plan->parallel_safe = parallel_safe;
1643
1644 return plan;
1645 }
1646
1647 /*
1648 * change_plan_targetlist
1649 * Externally available wrapper for inject_projection_plan.
1650 *
1651 * This is meant for use by FDW plan-generation functions, which might
1652 * want to adjust the tlist computed by some subplan tree. In general,
1653 * a Result node is needed to compute the new tlist, but we can optimize
1654 * some cases.
1655 *
1656 * In most cases, tlist_parallel_safe can just be passed as the parallel_safe
1657 * flag of the FDW's own Path node.
1658 */
1659 Plan *
change_plan_targetlist(Plan * subplan,List * tlist,bool tlist_parallel_safe)1660 change_plan_targetlist(Plan *subplan, List *tlist, bool tlist_parallel_safe)
1661 {
1662 /*
1663 * If the top plan node can't do projections and its existing target list
1664 * isn't already what we need, we need to add a Result node to help it
1665 * along.
1666 */
1667 if (!is_projection_capable_plan(subplan) &&
1668 !tlist_same_exprs(tlist, subplan->targetlist))
1669 subplan = inject_projection_plan(subplan, tlist,
1670 subplan->parallel_safe &&
1671 tlist_parallel_safe);
1672 else
1673 {
1674 /* Else we can just replace the plan node's tlist */
1675 subplan->targetlist = tlist;
1676 subplan->parallel_safe &= tlist_parallel_safe;
1677 }
1678 return subplan;
1679 }
1680
1681 /*
1682 * create_sort_plan
1683 *
1684 * Create a Sort plan for 'best_path' and (recursively) plans
1685 * for its subpaths.
1686 */
1687 static Sort *
create_sort_plan(PlannerInfo * root,SortPath * best_path,int flags)1688 create_sort_plan(PlannerInfo *root, SortPath *best_path, int flags)
1689 {
1690 Sort *plan;
1691 Plan *subplan;
1692
1693 /*
1694 * We don't want any excess columns in the sorted tuples, so request a
1695 * smaller tlist. Otherwise, since Sort doesn't project, tlist
1696 * requirements pass through.
1697 */
1698 subplan = create_plan_recurse(root, best_path->subpath,
1699 flags | CP_SMALL_TLIST);
1700
1701 plan = make_sort_from_pathkeys(subplan, best_path->path.pathkeys);
1702
1703 copy_generic_path_info(&plan->plan, (Path *) best_path);
1704
1705 return plan;
1706 }
1707
1708 /*
1709 * create_group_plan
1710 *
1711 * Create a Group plan for 'best_path' and (recursively) plans
1712 * for its subpaths.
1713 */
1714 static Group *
create_group_plan(PlannerInfo * root,GroupPath * best_path)1715 create_group_plan(PlannerInfo *root, GroupPath *best_path)
1716 {
1717 Group *plan;
1718 Plan *subplan;
1719 List *tlist;
1720 List *quals;
1721
1722 /*
1723 * Group can project, so no need to be terribly picky about child tlist,
1724 * but we do need grouping columns to be available
1725 */
1726 subplan = create_plan_recurse(root, best_path->subpath, CP_LABEL_TLIST);
1727
1728 tlist = build_path_tlist(root, &best_path->path);
1729
1730 quals = order_qual_clauses(root, best_path->qual);
1731
1732 plan = make_group(tlist,
1733 quals,
1734 list_length(best_path->groupClause),
1735 extract_grouping_cols(best_path->groupClause,
1736 subplan->targetlist),
1737 extract_grouping_ops(best_path->groupClause),
1738 subplan);
1739
1740 copy_generic_path_info(&plan->plan, (Path *) best_path);
1741
1742 return plan;
1743 }
1744
1745 /*
1746 * create_upper_unique_plan
1747 *
1748 * Create a Unique plan for 'best_path' and (recursively) plans
1749 * for its subpaths.
1750 */
1751 static Unique *
create_upper_unique_plan(PlannerInfo * root,UpperUniquePath * best_path,int flags)1752 create_upper_unique_plan(PlannerInfo *root, UpperUniquePath *best_path, int flags)
1753 {
1754 Unique *plan;
1755 Plan *subplan;
1756
1757 /*
1758 * Unique doesn't project, so tlist requirements pass through; moreover we
1759 * need grouping columns to be labeled.
1760 */
1761 subplan = create_plan_recurse(root, best_path->subpath,
1762 flags | CP_LABEL_TLIST);
1763
1764 plan = make_unique_from_pathkeys(subplan,
1765 best_path->path.pathkeys,
1766 best_path->numkeys);
1767
1768 copy_generic_path_info(&plan->plan, (Path *) best_path);
1769
1770 return plan;
1771 }
1772
1773 /*
1774 * create_agg_plan
1775 *
1776 * Create an Agg plan for 'best_path' and (recursively) plans
1777 * for its subpaths.
1778 */
1779 static Agg *
create_agg_plan(PlannerInfo * root,AggPath * best_path)1780 create_agg_plan(PlannerInfo *root, AggPath *best_path)
1781 {
1782 Agg *plan;
1783 Plan *subplan;
1784 List *tlist;
1785 List *quals;
1786
1787 /*
1788 * Agg can project, so no need to be terribly picky about child tlist, but
1789 * we do need grouping columns to be available
1790 */
1791 subplan = create_plan_recurse(root, best_path->subpath, CP_LABEL_TLIST);
1792
1793 tlist = build_path_tlist(root, &best_path->path);
1794
1795 quals = order_qual_clauses(root, best_path->qual);
1796
1797 plan = make_agg(tlist, quals,
1798 best_path->aggstrategy,
1799 best_path->aggsplit,
1800 list_length(best_path->groupClause),
1801 extract_grouping_cols(best_path->groupClause,
1802 subplan->targetlist),
1803 extract_grouping_ops(best_path->groupClause),
1804 NIL,
1805 NIL,
1806 best_path->numGroups,
1807 subplan);
1808
1809 copy_generic_path_info(&plan->plan, (Path *) best_path);
1810
1811 return plan;
1812 }
1813
1814 /*
1815 * Given a groupclause for a collection of grouping sets, produce the
1816 * corresponding groupColIdx.
1817 *
1818 * root->grouping_map maps the tleSortGroupRef to the actual column position in
1819 * the input tuple. So we get the ref from the entries in the groupclause and
1820 * look them up there.
1821 */
1822 static AttrNumber *
remap_groupColIdx(PlannerInfo * root,List * groupClause)1823 remap_groupColIdx(PlannerInfo *root, List *groupClause)
1824 {
1825 AttrNumber *grouping_map = root->grouping_map;
1826 AttrNumber *new_grpColIdx;
1827 ListCell *lc;
1828 int i;
1829
1830 Assert(grouping_map);
1831
1832 new_grpColIdx = palloc0(sizeof(AttrNumber) * list_length(groupClause));
1833
1834 i = 0;
1835 foreach(lc, groupClause)
1836 {
1837 SortGroupClause *clause = lfirst(lc);
1838
1839 new_grpColIdx[i++] = grouping_map[clause->tleSortGroupRef];
1840 }
1841
1842 return new_grpColIdx;
1843 }
1844
1845 /*
1846 * create_groupingsets_plan
1847 * Create a plan for 'best_path' and (recursively) plans
1848 * for its subpaths.
1849 *
1850 * What we emit is an Agg plan with some vestigial Agg and Sort nodes
1851 * hanging off the side. The top Agg implements the last grouping set
1852 * specified in the GroupingSetsPath, and any additional grouping sets
1853 * each give rise to a subsidiary Agg and Sort node in the top Agg's
1854 * "chain" list. These nodes don't participate in the plan directly,
1855 * but they are a convenient way to represent the required data for
1856 * the extra steps.
1857 *
1858 * Returns a Plan node.
1859 */
1860 static Plan *
create_groupingsets_plan(PlannerInfo * root,GroupingSetsPath * best_path)1861 create_groupingsets_plan(PlannerInfo *root, GroupingSetsPath *best_path)
1862 {
1863 Agg *plan;
1864 Plan *subplan;
1865 List *rollups = best_path->rollups;
1866 AttrNumber *grouping_map;
1867 int maxref;
1868 List *chain;
1869 ListCell *lc;
1870
1871 /* Shouldn't get here without grouping sets */
1872 Assert(root->parse->groupingSets);
1873 Assert(rollups != NIL);
1874
1875 /*
1876 * Agg can project, so no need to be terribly picky about child tlist, but
1877 * we do need grouping columns to be available
1878 */
1879 subplan = create_plan_recurse(root, best_path->subpath, CP_LABEL_TLIST);
1880
1881 /*
1882 * Compute the mapping from tleSortGroupRef to column index in the child's
1883 * tlist. First, identify max SortGroupRef in groupClause, for array
1884 * sizing.
1885 */
1886 maxref = 0;
1887 foreach(lc, root->parse->groupClause)
1888 {
1889 SortGroupClause *gc = (SortGroupClause *) lfirst(lc);
1890
1891 if (gc->tleSortGroupRef > maxref)
1892 maxref = gc->tleSortGroupRef;
1893 }
1894
1895 grouping_map = (AttrNumber *) palloc0((maxref + 1) * sizeof(AttrNumber));
1896
1897 /* Now look up the column numbers in the child's tlist */
1898 foreach(lc, root->parse->groupClause)
1899 {
1900 SortGroupClause *gc = (SortGroupClause *) lfirst(lc);
1901 TargetEntry *tle = get_sortgroupclause_tle(gc, subplan->targetlist);
1902
1903 grouping_map[gc->tleSortGroupRef] = tle->resno;
1904 }
1905
1906 /*
1907 * During setrefs.c, we'll need the grouping_map to fix up the cols lists
1908 * in GroupingFunc nodes. Save it for setrefs.c to use.
1909 *
1910 * This doesn't work if we're in an inheritance subtree (see notes in
1911 * create_modifytable_plan). Fortunately we can't be because there would
1912 * never be grouping in an UPDATE/DELETE; but let's Assert that.
1913 */
1914 Assert(!root->hasInheritedTarget);
1915 Assert(root->grouping_map == NULL);
1916 root->grouping_map = grouping_map;
1917
1918 /*
1919 * Generate the side nodes that describe the other sort and group
1920 * operations besides the top one. Note that we don't worry about putting
1921 * accurate cost estimates in the side nodes; only the topmost Agg node's
1922 * costs will be shown by EXPLAIN.
1923 */
1924 chain = NIL;
1925 if (list_length(rollups) > 1)
1926 {
1927 ListCell *lc2 = lnext(list_head(rollups));
1928 bool is_first_sort = ((RollupData *) linitial(rollups))->is_hashed;
1929
1930 for_each_cell(lc, lc2)
1931 {
1932 RollupData *rollup = lfirst(lc);
1933 AttrNumber *new_grpColIdx;
1934 Plan *sort_plan = NULL;
1935 Plan *agg_plan;
1936 AggStrategy strat;
1937
1938 new_grpColIdx = remap_groupColIdx(root, rollup->groupClause);
1939
1940 if (!rollup->is_hashed && !is_first_sort)
1941 {
1942 sort_plan = (Plan *)
1943 make_sort_from_groupcols(rollup->groupClause,
1944 new_grpColIdx,
1945 subplan);
1946 }
1947
1948 if (!rollup->is_hashed)
1949 is_first_sort = false;
1950
1951 if (rollup->is_hashed)
1952 strat = AGG_HASHED;
1953 else if (list_length(linitial(rollup->gsets)) == 0)
1954 strat = AGG_PLAIN;
1955 else
1956 strat = AGG_SORTED;
1957
1958 agg_plan = (Plan *) make_agg(NIL,
1959 NIL,
1960 strat,
1961 AGGSPLIT_SIMPLE,
1962 list_length((List *) linitial(rollup->gsets)),
1963 new_grpColIdx,
1964 extract_grouping_ops(rollup->groupClause),
1965 rollup->gsets,
1966 NIL,
1967 rollup->numGroups,
1968 sort_plan);
1969
1970 /*
1971 * Remove stuff we don't need to avoid bloating debug output.
1972 */
1973 if (sort_plan)
1974 {
1975 sort_plan->targetlist = NIL;
1976 sort_plan->lefttree = NULL;
1977 }
1978
1979 chain = lappend(chain, agg_plan);
1980 }
1981 }
1982
1983 /*
1984 * Now make the real Agg node
1985 */
1986 {
1987 RollupData *rollup = linitial(rollups);
1988 AttrNumber *top_grpColIdx;
1989 int numGroupCols;
1990
1991 top_grpColIdx = remap_groupColIdx(root, rollup->groupClause);
1992
1993 numGroupCols = list_length((List *) linitial(rollup->gsets));
1994
1995 plan = make_agg(build_path_tlist(root, &best_path->path),
1996 best_path->qual,
1997 best_path->aggstrategy,
1998 AGGSPLIT_SIMPLE,
1999 numGroupCols,
2000 top_grpColIdx,
2001 extract_grouping_ops(rollup->groupClause),
2002 rollup->gsets,
2003 chain,
2004 rollup->numGroups,
2005 subplan);
2006
2007 /* Copy cost data from Path to Plan */
2008 copy_generic_path_info(&plan->plan, &best_path->path);
2009 }
2010
2011 return (Plan *) plan;
2012 }
2013
2014 /*
2015 * create_minmaxagg_plan
2016 *
2017 * Create a Result plan for 'best_path' and (recursively) plans
2018 * for its subpaths.
2019 */
2020 static Result *
create_minmaxagg_plan(PlannerInfo * root,MinMaxAggPath * best_path)2021 create_minmaxagg_plan(PlannerInfo *root, MinMaxAggPath *best_path)
2022 {
2023 Result *plan;
2024 List *tlist;
2025 ListCell *lc;
2026
2027 /* Prepare an InitPlan for each aggregate's subquery. */
2028 foreach(lc, best_path->mmaggregates)
2029 {
2030 MinMaxAggInfo *mminfo = (MinMaxAggInfo *) lfirst(lc);
2031 PlannerInfo *subroot = mminfo->subroot;
2032 Query *subparse = subroot->parse;
2033 Plan *plan;
2034
2035 /*
2036 * Generate the plan for the subquery. We already have a Path, but we
2037 * have to convert it to a Plan and attach a LIMIT node above it.
2038 * Since we are entering a different planner context (subroot),
2039 * recurse to create_plan not create_plan_recurse.
2040 */
2041 plan = create_plan(subroot, mminfo->path);
2042
2043 plan = (Plan *) make_limit(plan,
2044 subparse->limitOffset,
2045 subparse->limitCount);
2046
2047 /* Must apply correct cost/width data to Limit node */
2048 plan->startup_cost = mminfo->path->startup_cost;
2049 plan->total_cost = mminfo->pathcost;
2050 plan->plan_rows = 1;
2051 plan->plan_width = mminfo->path->pathtarget->width;
2052 plan->parallel_aware = false;
2053 plan->parallel_safe = mminfo->path->parallel_safe;
2054
2055 /* Convert the plan into an InitPlan in the outer query. */
2056 SS_make_initplan_from_plan(root, subroot, plan, mminfo->param);
2057 }
2058
2059 /* Generate the output plan --- basically just a Result */
2060 tlist = build_path_tlist(root, &best_path->path);
2061
2062 plan = make_result(tlist, (Node *) best_path->quals, NULL);
2063
2064 copy_generic_path_info(&plan->plan, (Path *) best_path);
2065
2066 /*
2067 * During setrefs.c, we'll need to replace references to the Agg nodes
2068 * with InitPlan output params. (We can't just do that locally in the
2069 * MinMaxAgg node, because path nodes above here may have Agg references
2070 * as well.) Save the mmaggregates list to tell setrefs.c to do that.
2071 *
2072 * This doesn't work if we're in an inheritance subtree (see notes in
2073 * create_modifytable_plan). Fortunately we can't be because there would
2074 * never be aggregates in an UPDATE/DELETE; but let's Assert that.
2075 */
2076 Assert(!root->hasInheritedTarget);
2077 Assert(root->minmax_aggs == NIL);
2078 root->minmax_aggs = best_path->mmaggregates;
2079
2080 return plan;
2081 }
2082
2083 /*
2084 * create_windowagg_plan
2085 *
2086 * Create a WindowAgg plan for 'best_path' and (recursively) plans
2087 * for its subpaths.
2088 */
2089 static WindowAgg *
create_windowagg_plan(PlannerInfo * root,WindowAggPath * best_path)2090 create_windowagg_plan(PlannerInfo *root, WindowAggPath *best_path)
2091 {
2092 WindowAgg *plan;
2093 WindowClause *wc = best_path->winclause;
2094 Plan *subplan;
2095 List *tlist;
2096 int numsortkeys;
2097 AttrNumber *sortColIdx;
2098 Oid *sortOperators;
2099 Oid *collations;
2100 bool *nullsFirst;
2101 int partNumCols;
2102 AttrNumber *partColIdx;
2103 Oid *partOperators;
2104 int ordNumCols;
2105 AttrNumber *ordColIdx;
2106 Oid *ordOperators;
2107
2108 /*
2109 * Choice of tlist here is motivated by the fact that WindowAgg will be
2110 * storing the input rows of window frames in a tuplestore; it therefore
2111 * behooves us to request a small tlist to avoid wasting space. We do of
2112 * course need grouping columns to be available.
2113 */
2114 subplan = create_plan_recurse(root, best_path->subpath,
2115 CP_LABEL_TLIST | CP_SMALL_TLIST);
2116
2117 tlist = build_path_tlist(root, &best_path->path);
2118
2119 /*
2120 * We shouldn't need to actually sort, but it's convenient to use
2121 * prepare_sort_from_pathkeys to identify the input's sort columns.
2122 */
2123 subplan = prepare_sort_from_pathkeys(subplan,
2124 best_path->winpathkeys,
2125 NULL,
2126 NULL,
2127 false,
2128 &numsortkeys,
2129 &sortColIdx,
2130 &sortOperators,
2131 &collations,
2132 &nullsFirst);
2133
2134 /* Now deconstruct that into partition and ordering portions */
2135 get_column_info_for_window(root,
2136 wc,
2137 subplan->targetlist,
2138 numsortkeys,
2139 sortColIdx,
2140 &partNumCols,
2141 &partColIdx,
2142 &partOperators,
2143 &ordNumCols,
2144 &ordColIdx,
2145 &ordOperators);
2146
2147 /* And finally we can make the WindowAgg node */
2148 plan = make_windowagg(tlist,
2149 wc->winref,
2150 partNumCols,
2151 partColIdx,
2152 partOperators,
2153 ordNumCols,
2154 ordColIdx,
2155 ordOperators,
2156 wc->frameOptions,
2157 wc->startOffset,
2158 wc->endOffset,
2159 subplan);
2160
2161 copy_generic_path_info(&plan->plan, (Path *) best_path);
2162
2163 return plan;
2164 }
2165
2166 /*
2167 * get_column_info_for_window
2168 * Get the partitioning/ordering column numbers and equality operators
2169 * for a WindowAgg node.
2170 *
2171 * This depends on the behavior of planner.c's make_pathkeys_for_window!
2172 *
2173 * We are given the target WindowClause and an array of the input column
2174 * numbers associated with the resulting pathkeys. In the easy case, there
2175 * are the same number of pathkey columns as partitioning + ordering columns
2176 * and we just have to copy some data around. However, it's possible that
2177 * some of the original partitioning + ordering columns were eliminated as
2178 * redundant during the transformation to pathkeys. (This can happen even
2179 * though the parser gets rid of obvious duplicates. A typical scenario is a
2180 * window specification "PARTITION BY x ORDER BY y" coupled with a clause
2181 * "WHERE x = y" that causes the two sort columns to be recognized as
2182 * redundant.) In that unusual case, we have to work a lot harder to
2183 * determine which keys are significant.
2184 *
2185 * The method used here is a bit brute-force: add the sort columns to a list
2186 * one at a time and note when the resulting pathkey list gets longer. But
2187 * it's a sufficiently uncommon case that a faster way doesn't seem worth
2188 * the amount of code refactoring that'd be needed.
2189 */
2190 static void
get_column_info_for_window(PlannerInfo * root,WindowClause * wc,List * tlist,int numSortCols,AttrNumber * sortColIdx,int * partNumCols,AttrNumber ** partColIdx,Oid ** partOperators,int * ordNumCols,AttrNumber ** ordColIdx,Oid ** ordOperators)2191 get_column_info_for_window(PlannerInfo *root, WindowClause *wc, List *tlist,
2192 int numSortCols, AttrNumber *sortColIdx,
2193 int *partNumCols,
2194 AttrNumber **partColIdx,
2195 Oid **partOperators,
2196 int *ordNumCols,
2197 AttrNumber **ordColIdx,
2198 Oid **ordOperators)
2199 {
2200 int numPart = list_length(wc->partitionClause);
2201 int numOrder = list_length(wc->orderClause);
2202
2203 if (numSortCols == numPart + numOrder)
2204 {
2205 /* easy case */
2206 *partNumCols = numPart;
2207 *partColIdx = sortColIdx;
2208 *partOperators = extract_grouping_ops(wc->partitionClause);
2209 *ordNumCols = numOrder;
2210 *ordColIdx = sortColIdx + numPart;
2211 *ordOperators = extract_grouping_ops(wc->orderClause);
2212 }
2213 else
2214 {
2215 List *sortclauses;
2216 List *pathkeys;
2217 int scidx;
2218 ListCell *lc;
2219
2220 /* first, allocate what's certainly enough space for the arrays */
2221 *partNumCols = 0;
2222 *partColIdx = (AttrNumber *) palloc(numPart * sizeof(AttrNumber));
2223 *partOperators = (Oid *) palloc(numPart * sizeof(Oid));
2224 *ordNumCols = 0;
2225 *ordColIdx = (AttrNumber *) palloc(numOrder * sizeof(AttrNumber));
2226 *ordOperators = (Oid *) palloc(numOrder * sizeof(Oid));
2227 sortclauses = NIL;
2228 pathkeys = NIL;
2229 scidx = 0;
2230 foreach(lc, wc->partitionClause)
2231 {
2232 SortGroupClause *sgc = (SortGroupClause *) lfirst(lc);
2233 List *new_pathkeys;
2234
2235 sortclauses = lappend(sortclauses, sgc);
2236 new_pathkeys = make_pathkeys_for_sortclauses(root,
2237 sortclauses,
2238 tlist);
2239 if (list_length(new_pathkeys) > list_length(pathkeys))
2240 {
2241 /* this sort clause is actually significant */
2242 (*partColIdx)[*partNumCols] = sortColIdx[scidx++];
2243 (*partOperators)[*partNumCols] = sgc->eqop;
2244 (*partNumCols)++;
2245 pathkeys = new_pathkeys;
2246 }
2247 }
2248 foreach(lc, wc->orderClause)
2249 {
2250 SortGroupClause *sgc = (SortGroupClause *) lfirst(lc);
2251 List *new_pathkeys;
2252
2253 sortclauses = lappend(sortclauses, sgc);
2254 new_pathkeys = make_pathkeys_for_sortclauses(root,
2255 sortclauses,
2256 tlist);
2257 if (list_length(new_pathkeys) > list_length(pathkeys))
2258 {
2259 /* this sort clause is actually significant */
2260 (*ordColIdx)[*ordNumCols] = sortColIdx[scidx++];
2261 (*ordOperators)[*ordNumCols] = sgc->eqop;
2262 (*ordNumCols)++;
2263 pathkeys = new_pathkeys;
2264 }
2265 }
2266 /* complain if we didn't eat exactly the right number of sort cols */
2267 if (scidx != numSortCols)
2268 elog(ERROR, "failed to deconstruct sort operators into partitioning/ordering operators");
2269 }
2270 }
2271
2272 /*
2273 * create_setop_plan
2274 *
2275 * Create a SetOp plan for 'best_path' and (recursively) plans
2276 * for its subpaths.
2277 */
2278 static SetOp *
create_setop_plan(PlannerInfo * root,SetOpPath * best_path,int flags)2279 create_setop_plan(PlannerInfo *root, SetOpPath *best_path, int flags)
2280 {
2281 SetOp *plan;
2282 Plan *subplan;
2283 long numGroups;
2284
2285 /*
2286 * SetOp doesn't project, so tlist requirements pass through; moreover we
2287 * need grouping columns to be labeled.
2288 */
2289 subplan = create_plan_recurse(root, best_path->subpath,
2290 flags | CP_LABEL_TLIST);
2291
2292 /* Convert numGroups to long int --- but 'ware overflow! */
2293 numGroups = (long) Min(best_path->numGroups, (double) LONG_MAX);
2294
2295 plan = make_setop(best_path->cmd,
2296 best_path->strategy,
2297 subplan,
2298 best_path->distinctList,
2299 best_path->flagColIdx,
2300 best_path->firstFlag,
2301 numGroups);
2302
2303 copy_generic_path_info(&plan->plan, (Path *) best_path);
2304
2305 return plan;
2306 }
2307
2308 /*
2309 * create_recursiveunion_plan
2310 *
2311 * Create a RecursiveUnion plan for 'best_path' and (recursively) plans
2312 * for its subpaths.
2313 */
2314 static RecursiveUnion *
create_recursiveunion_plan(PlannerInfo * root,RecursiveUnionPath * best_path)2315 create_recursiveunion_plan(PlannerInfo *root, RecursiveUnionPath *best_path)
2316 {
2317 RecursiveUnion *plan;
2318 Plan *leftplan;
2319 Plan *rightplan;
2320 List *tlist;
2321 long numGroups;
2322
2323 /* Need both children to produce same tlist, so force it */
2324 leftplan = create_plan_recurse(root, best_path->leftpath, CP_EXACT_TLIST);
2325 rightplan = create_plan_recurse(root, best_path->rightpath, CP_EXACT_TLIST);
2326
2327 tlist = build_path_tlist(root, &best_path->path);
2328
2329 /* Convert numGroups to long int --- but 'ware overflow! */
2330 numGroups = (long) Min(best_path->numGroups, (double) LONG_MAX);
2331
2332 plan = make_recursive_union(tlist,
2333 leftplan,
2334 rightplan,
2335 best_path->wtParam,
2336 best_path->distinctList,
2337 numGroups);
2338
2339 copy_generic_path_info(&plan->plan, (Path *) best_path);
2340
2341 return plan;
2342 }
2343
2344 /*
2345 * create_lockrows_plan
2346 *
2347 * Create a LockRows plan for 'best_path' and (recursively) plans
2348 * for its subpaths.
2349 */
2350 static LockRows *
create_lockrows_plan(PlannerInfo * root,LockRowsPath * best_path,int flags)2351 create_lockrows_plan(PlannerInfo *root, LockRowsPath *best_path,
2352 int flags)
2353 {
2354 LockRows *plan;
2355 Plan *subplan;
2356
2357 /* LockRows doesn't project, so tlist requirements pass through */
2358 subplan = create_plan_recurse(root, best_path->subpath, flags);
2359
2360 plan = make_lockrows(subplan, best_path->rowMarks, best_path->epqParam);
2361
2362 copy_generic_path_info(&plan->plan, (Path *) best_path);
2363
2364 return plan;
2365 }
2366
2367 /*
2368 * create_modifytable_plan
2369 * Create a ModifyTable plan for 'best_path'.
2370 *
2371 * Returns a Plan node.
2372 */
2373 static ModifyTable *
create_modifytable_plan(PlannerInfo * root,ModifyTablePath * best_path)2374 create_modifytable_plan(PlannerInfo *root, ModifyTablePath *best_path)
2375 {
2376 ModifyTable *plan;
2377 List *subplans = NIL;
2378 ListCell *subpaths,
2379 *subroots;
2380
2381 /* Build the plan for each input path */
2382 forboth(subpaths, best_path->subpaths,
2383 subroots, best_path->subroots)
2384 {
2385 Path *subpath = (Path *) lfirst(subpaths);
2386 PlannerInfo *subroot = (PlannerInfo *) lfirst(subroots);
2387 Plan *subplan;
2388
2389 /*
2390 * In an inherited UPDATE/DELETE, reference the per-child modified
2391 * subroot while creating Plans from Paths for the child rel. This is
2392 * a kluge, but otherwise it's too hard to ensure that Plan creation
2393 * functions (particularly in FDWs) don't depend on the contents of
2394 * "root" matching what they saw at Path creation time. The main
2395 * downside is that creation functions for Plans that might appear
2396 * below a ModifyTable cannot expect to modify the contents of "root"
2397 * and have it "stick" for subsequent processing such as setrefs.c.
2398 * That's not great, but it seems better than the alternative.
2399 */
2400 subplan = create_plan_recurse(subroot, subpath, CP_EXACT_TLIST);
2401
2402 /* Transfer resname/resjunk labeling, too, to keep executor happy */
2403 apply_tlist_labeling(subplan->targetlist, subroot->processed_tlist);
2404
2405 subplans = lappend(subplans, subplan);
2406 }
2407
2408 plan = make_modifytable(root,
2409 best_path->operation,
2410 best_path->canSetTag,
2411 best_path->nominalRelation,
2412 best_path->partitioned_rels,
2413 best_path->resultRelations,
2414 subplans,
2415 best_path->withCheckOptionLists,
2416 best_path->returningLists,
2417 best_path->rowMarks,
2418 best_path->onconflict,
2419 best_path->epqParam);
2420
2421 copy_generic_path_info(&plan->plan, &best_path->path);
2422
2423 return plan;
2424 }
2425
2426 /*
2427 * create_limit_plan
2428 *
2429 * Create a Limit plan for 'best_path' and (recursively) plans
2430 * for its subpaths.
2431 */
2432 static Limit *
create_limit_plan(PlannerInfo * root,LimitPath * best_path,int flags)2433 create_limit_plan(PlannerInfo *root, LimitPath *best_path, int flags)
2434 {
2435 Limit *plan;
2436 Plan *subplan;
2437
2438 /* Limit doesn't project, so tlist requirements pass through */
2439 subplan = create_plan_recurse(root, best_path->subpath, flags);
2440
2441 plan = make_limit(subplan,
2442 best_path->limitOffset,
2443 best_path->limitCount);
2444
2445 copy_generic_path_info(&plan->plan, (Path *) best_path);
2446
2447 return plan;
2448 }
2449
2450
2451 /*****************************************************************************
2452 *
2453 * BASE-RELATION SCAN METHODS
2454 *
2455 *****************************************************************************/
2456
2457
2458 /*
2459 * create_seqscan_plan
2460 * Returns a seqscan plan for the base relation scanned by 'best_path'
2461 * with restriction clauses 'scan_clauses' and targetlist 'tlist'.
2462 */
2463 static SeqScan *
create_seqscan_plan(PlannerInfo * root,Path * best_path,List * tlist,List * scan_clauses)2464 create_seqscan_plan(PlannerInfo *root, Path *best_path,
2465 List *tlist, List *scan_clauses)
2466 {
2467 SeqScan *scan_plan;
2468 Index scan_relid = best_path->parent->relid;
2469
2470 /* it should be a base rel... */
2471 Assert(scan_relid > 0);
2472 Assert(best_path->parent->rtekind == RTE_RELATION);
2473
2474 /* Sort clauses into best execution order */
2475 scan_clauses = order_qual_clauses(root, scan_clauses);
2476
2477 /* Reduce RestrictInfo list to bare expressions; ignore pseudoconstants */
2478 scan_clauses = extract_actual_clauses(scan_clauses, false);
2479
2480 /* Replace any outer-relation variables with nestloop params */
2481 if (best_path->param_info)
2482 {
2483 scan_clauses = (List *)
2484 replace_nestloop_params(root, (Node *) scan_clauses);
2485 }
2486
2487 scan_plan = make_seqscan(tlist,
2488 scan_clauses,
2489 scan_relid);
2490
2491 copy_generic_path_info(&scan_plan->plan, best_path);
2492
2493 return scan_plan;
2494 }
2495
2496 /*
2497 * create_samplescan_plan
2498 * Returns a samplescan plan for the base relation scanned by 'best_path'
2499 * with restriction clauses 'scan_clauses' and targetlist 'tlist'.
2500 */
2501 static SampleScan *
create_samplescan_plan(PlannerInfo * root,Path * best_path,List * tlist,List * scan_clauses)2502 create_samplescan_plan(PlannerInfo *root, Path *best_path,
2503 List *tlist, List *scan_clauses)
2504 {
2505 SampleScan *scan_plan;
2506 Index scan_relid = best_path->parent->relid;
2507 RangeTblEntry *rte;
2508 TableSampleClause *tsc;
2509
2510 /* it should be a base rel with a tablesample clause... */
2511 Assert(scan_relid > 0);
2512 rte = planner_rt_fetch(scan_relid, root);
2513 Assert(rte->rtekind == RTE_RELATION);
2514 tsc = rte->tablesample;
2515 Assert(tsc != NULL);
2516
2517 /* Sort clauses into best execution order */
2518 scan_clauses = order_qual_clauses(root, scan_clauses);
2519
2520 /* Reduce RestrictInfo list to bare expressions; ignore pseudoconstants */
2521 scan_clauses = extract_actual_clauses(scan_clauses, false);
2522
2523 /* Replace any outer-relation variables with nestloop params */
2524 if (best_path->param_info)
2525 {
2526 scan_clauses = (List *)
2527 replace_nestloop_params(root, (Node *) scan_clauses);
2528 tsc = (TableSampleClause *)
2529 replace_nestloop_params(root, (Node *) tsc);
2530 }
2531
2532 scan_plan = make_samplescan(tlist,
2533 scan_clauses,
2534 scan_relid,
2535 tsc);
2536
2537 copy_generic_path_info(&scan_plan->scan.plan, best_path);
2538
2539 return scan_plan;
2540 }
2541
2542 /*
2543 * create_indexscan_plan
2544 * Returns an indexscan plan for the base relation scanned by 'best_path'
2545 * with restriction clauses 'scan_clauses' and targetlist 'tlist'.
2546 *
2547 * We use this for both plain IndexScans and IndexOnlyScans, because the
2548 * qual preprocessing work is the same for both. Note that the caller tells
2549 * us which to build --- we don't look at best_path->path.pathtype, because
2550 * create_bitmap_subplan needs to be able to override the prior decision.
2551 */
2552 static Scan *
create_indexscan_plan(PlannerInfo * root,IndexPath * best_path,List * tlist,List * scan_clauses,bool indexonly)2553 create_indexscan_plan(PlannerInfo *root,
2554 IndexPath *best_path,
2555 List *tlist,
2556 List *scan_clauses,
2557 bool indexonly)
2558 {
2559 Scan *scan_plan;
2560 List *indexquals = best_path->indexquals;
2561 List *indexorderbys = best_path->indexorderbys;
2562 Index baserelid = best_path->path.parent->relid;
2563 Oid indexoid = best_path->indexinfo->indexoid;
2564 List *qpqual;
2565 List *stripped_indexquals;
2566 List *fixed_indexquals;
2567 List *fixed_indexorderbys;
2568 List *indexorderbyops = NIL;
2569 ListCell *l;
2570
2571 /* it should be a base rel... */
2572 Assert(baserelid > 0);
2573 Assert(best_path->path.parent->rtekind == RTE_RELATION);
2574
2575 /*
2576 * Build "stripped" indexquals structure (no RestrictInfos) to pass to
2577 * executor as indexqualorig
2578 */
2579 stripped_indexquals = get_actual_clauses(indexquals);
2580
2581 /*
2582 * The executor needs a copy with the indexkey on the left of each clause
2583 * and with index Vars substituted for table ones.
2584 */
2585 fixed_indexquals = fix_indexqual_references(root, best_path);
2586
2587 /*
2588 * Likewise fix up index attr references in the ORDER BY expressions.
2589 */
2590 fixed_indexorderbys = fix_indexorderby_references(root, best_path);
2591
2592 /*
2593 * The qpqual list must contain all restrictions not automatically handled
2594 * by the index, other than pseudoconstant clauses which will be handled
2595 * by a separate gating plan node. All the predicates in the indexquals
2596 * will be checked (either by the index itself, or by nodeIndexscan.c),
2597 * but if there are any "special" operators involved then they must be
2598 * included in qpqual. The upshot is that qpqual must contain
2599 * scan_clauses minus whatever appears in indexquals.
2600 *
2601 * In normal cases simple pointer equality checks will be enough to spot
2602 * duplicate RestrictInfos, so we try that first.
2603 *
2604 * Another common case is that a scan_clauses entry is generated from the
2605 * same EquivalenceClass as some indexqual, and is therefore redundant
2606 * with it, though not equal. (This happens when indxpath.c prefers a
2607 * different derived equality than what generate_join_implied_equalities
2608 * picked for a parameterized scan's ppi_clauses.)
2609 *
2610 * In some situations (particularly with OR'd index conditions) we may
2611 * have scan_clauses that are not equal to, but are logically implied by,
2612 * the index quals; so we also try a predicate_implied_by() check to see
2613 * if we can discard quals that way. (predicate_implied_by assumes its
2614 * first input contains only immutable functions, so we have to check
2615 * that.)
2616 *
2617 * Note: if you change this bit of code you should also look at
2618 * extract_nonindex_conditions() in costsize.c.
2619 */
2620 qpqual = NIL;
2621 foreach(l, scan_clauses)
2622 {
2623 RestrictInfo *rinfo = lfirst_node(RestrictInfo, l);
2624
2625 if (rinfo->pseudoconstant)
2626 continue; /* we may drop pseudoconstants here */
2627 if (list_member_ptr(indexquals, rinfo))
2628 continue; /* simple duplicate */
2629 if (is_redundant_derived_clause(rinfo, indexquals))
2630 continue; /* derived from same EquivalenceClass */
2631 if (!contain_mutable_functions((Node *) rinfo->clause) &&
2632 predicate_implied_by(list_make1(rinfo->clause), indexquals, false))
2633 continue; /* provably implied by indexquals */
2634 qpqual = lappend(qpqual, rinfo);
2635 }
2636
2637 /* Sort clauses into best execution order */
2638 qpqual = order_qual_clauses(root, qpqual);
2639
2640 /* Reduce RestrictInfo list to bare expressions; ignore pseudoconstants */
2641 qpqual = extract_actual_clauses(qpqual, false);
2642
2643 /*
2644 * We have to replace any outer-relation variables with nestloop params in
2645 * the indexqualorig, qpqual, and indexorderbyorig expressions. A bit
2646 * annoying to have to do this separately from the processing in
2647 * fix_indexqual_references --- rethink this when generalizing the inner
2648 * indexscan support. But note we can't really do this earlier because
2649 * it'd break the comparisons to predicates above ... (or would it? Those
2650 * wouldn't have outer refs)
2651 */
2652 if (best_path->path.param_info)
2653 {
2654 stripped_indexquals = (List *)
2655 replace_nestloop_params(root, (Node *) stripped_indexquals);
2656 qpqual = (List *)
2657 replace_nestloop_params(root, (Node *) qpqual);
2658 indexorderbys = (List *)
2659 replace_nestloop_params(root, (Node *) indexorderbys);
2660 }
2661
2662 /*
2663 * If there are ORDER BY expressions, look up the sort operators for their
2664 * result datatypes.
2665 */
2666 if (indexorderbys)
2667 {
2668 ListCell *pathkeyCell,
2669 *exprCell;
2670
2671 /*
2672 * PathKey contains OID of the btree opfamily we're sorting by, but
2673 * that's not quite enough because we need the expression's datatype
2674 * to look up the sort operator in the operator family.
2675 */
2676 Assert(list_length(best_path->path.pathkeys) == list_length(indexorderbys));
2677 forboth(pathkeyCell, best_path->path.pathkeys, exprCell, indexorderbys)
2678 {
2679 PathKey *pathkey = (PathKey *) lfirst(pathkeyCell);
2680 Node *expr = (Node *) lfirst(exprCell);
2681 Oid exprtype = exprType(expr);
2682 Oid sortop;
2683
2684 /* Get sort operator from opfamily */
2685 sortop = get_opfamily_member(pathkey->pk_opfamily,
2686 exprtype,
2687 exprtype,
2688 pathkey->pk_strategy);
2689 if (!OidIsValid(sortop))
2690 elog(ERROR, "missing operator %d(%u,%u) in opfamily %u",
2691 pathkey->pk_strategy, exprtype, exprtype, pathkey->pk_opfamily);
2692 indexorderbyops = lappend_oid(indexorderbyops, sortop);
2693 }
2694 }
2695
2696 /* Finally ready to build the plan node */
2697 if (indexonly)
2698 scan_plan = (Scan *) make_indexonlyscan(tlist,
2699 qpqual,
2700 baserelid,
2701 indexoid,
2702 fixed_indexquals,
2703 fixed_indexorderbys,
2704 best_path->indexinfo->indextlist,
2705 best_path->indexscandir);
2706 else
2707 scan_plan = (Scan *) make_indexscan(tlist,
2708 qpqual,
2709 baserelid,
2710 indexoid,
2711 fixed_indexquals,
2712 stripped_indexquals,
2713 fixed_indexorderbys,
2714 indexorderbys,
2715 indexorderbyops,
2716 best_path->indexscandir);
2717
2718 copy_generic_path_info(&scan_plan->plan, &best_path->path);
2719
2720 return scan_plan;
2721 }
2722
2723 /*
2724 * create_bitmap_scan_plan
2725 * Returns a bitmap scan plan for the base relation scanned by 'best_path'
2726 * with restriction clauses 'scan_clauses' and targetlist 'tlist'.
2727 */
2728 static BitmapHeapScan *
create_bitmap_scan_plan(PlannerInfo * root,BitmapHeapPath * best_path,List * tlist,List * scan_clauses)2729 create_bitmap_scan_plan(PlannerInfo *root,
2730 BitmapHeapPath *best_path,
2731 List *tlist,
2732 List *scan_clauses)
2733 {
2734 Index baserelid = best_path->path.parent->relid;
2735 Plan *bitmapqualplan;
2736 List *bitmapqualorig;
2737 List *indexquals;
2738 List *indexECs;
2739 List *qpqual;
2740 ListCell *l;
2741 BitmapHeapScan *scan_plan;
2742
2743 /* it should be a base rel... */
2744 Assert(baserelid > 0);
2745 Assert(best_path->path.parent->rtekind == RTE_RELATION);
2746
2747 /* Process the bitmapqual tree into a Plan tree and qual lists */
2748 bitmapqualplan = create_bitmap_subplan(root, best_path->bitmapqual,
2749 &bitmapqualorig, &indexquals,
2750 &indexECs);
2751
2752 if (best_path->path.parallel_aware)
2753 bitmap_subplan_mark_shared(bitmapqualplan);
2754
2755 /*
2756 * The qpqual list must contain all restrictions not automatically handled
2757 * by the index, other than pseudoconstant clauses which will be handled
2758 * by a separate gating plan node. All the predicates in the indexquals
2759 * will be checked (either by the index itself, or by
2760 * nodeBitmapHeapscan.c), but if there are any "special" operators
2761 * involved then they must be added to qpqual. The upshot is that qpqual
2762 * must contain scan_clauses minus whatever appears in indexquals.
2763 *
2764 * This loop is similar to the comparable code in create_indexscan_plan(),
2765 * but with some differences because it has to compare the scan clauses to
2766 * stripped (no RestrictInfos) indexquals. See comments there for more
2767 * info.
2768 *
2769 * In normal cases simple equal() checks will be enough to spot duplicate
2770 * clauses, so we try that first. We next see if the scan clause is
2771 * redundant with any top-level indexqual by virtue of being generated
2772 * from the same EC. After that, try predicate_implied_by().
2773 *
2774 * Unlike create_indexscan_plan(), the predicate_implied_by() test here is
2775 * useful for getting rid of qpquals that are implied by index predicates,
2776 * because the predicate conditions are included in the "indexquals"
2777 * returned by create_bitmap_subplan(). Bitmap scans have to do it that
2778 * way because predicate conditions need to be rechecked if the scan
2779 * becomes lossy, so they have to be included in bitmapqualorig.
2780 */
2781 qpqual = NIL;
2782 foreach(l, scan_clauses)
2783 {
2784 RestrictInfo *rinfo = lfirst_node(RestrictInfo, l);
2785 Node *clause = (Node *) rinfo->clause;
2786
2787 if (rinfo->pseudoconstant)
2788 continue; /* we may drop pseudoconstants here */
2789 if (list_member(indexquals, clause))
2790 continue; /* simple duplicate */
2791 if (rinfo->parent_ec && list_member_ptr(indexECs, rinfo->parent_ec))
2792 continue; /* derived from same EquivalenceClass */
2793 if (!contain_mutable_functions(clause) &&
2794 predicate_implied_by(list_make1(clause), indexquals, false))
2795 continue; /* provably implied by indexquals */
2796 qpqual = lappend(qpqual, rinfo);
2797 }
2798
2799 /* Sort clauses into best execution order */
2800 qpqual = order_qual_clauses(root, qpqual);
2801
2802 /* Reduce RestrictInfo list to bare expressions; ignore pseudoconstants */
2803 qpqual = extract_actual_clauses(qpqual, false);
2804
2805 /*
2806 * When dealing with special operators, we will at this point have
2807 * duplicate clauses in qpqual and bitmapqualorig. We may as well drop
2808 * 'em from bitmapqualorig, since there's no point in making the tests
2809 * twice.
2810 */
2811 bitmapqualorig = list_difference_ptr(bitmapqualorig, qpqual);
2812
2813 /*
2814 * We have to replace any outer-relation variables with nestloop params in
2815 * the qpqual and bitmapqualorig expressions. (This was already done for
2816 * expressions attached to plan nodes in the bitmapqualplan tree.)
2817 */
2818 if (best_path->path.param_info)
2819 {
2820 qpqual = (List *)
2821 replace_nestloop_params(root, (Node *) qpqual);
2822 bitmapqualorig = (List *)
2823 replace_nestloop_params(root, (Node *) bitmapqualorig);
2824 }
2825
2826 /* Finally ready to build the plan node */
2827 scan_plan = make_bitmap_heapscan(tlist,
2828 qpqual,
2829 bitmapqualplan,
2830 bitmapqualorig,
2831 baserelid);
2832
2833 copy_generic_path_info(&scan_plan->scan.plan, &best_path->path);
2834
2835 return scan_plan;
2836 }
2837
2838 /*
2839 * Given a bitmapqual tree, generate the Plan tree that implements it
2840 *
2841 * As byproducts, we also return in *qual and *indexqual the qual lists
2842 * (in implicit-AND form, without RestrictInfos) describing the original index
2843 * conditions and the generated indexqual conditions. (These are the same in
2844 * simple cases, but when special index operators are involved, the former
2845 * list includes the special conditions while the latter includes the actual
2846 * indexable conditions derived from them.) Both lists include partial-index
2847 * predicates, because we have to recheck predicates as well as index
2848 * conditions if the bitmap scan becomes lossy.
2849 *
2850 * In addition, we return a list of EquivalenceClass pointers for all the
2851 * top-level indexquals that were possibly-redundantly derived from ECs.
2852 * This allows removal of scan_clauses that are redundant with such quals.
2853 * (We do not attempt to detect such redundancies for quals that are within
2854 * OR subtrees. This could be done in a less hacky way if we returned the
2855 * indexquals in RestrictInfo form, but that would be slower and still pretty
2856 * messy, since we'd have to build new RestrictInfos in many cases.)
2857 */
2858 static Plan *
create_bitmap_subplan(PlannerInfo * root,Path * bitmapqual,List ** qual,List ** indexqual,List ** indexECs)2859 create_bitmap_subplan(PlannerInfo *root, Path *bitmapqual,
2860 List **qual, List **indexqual, List **indexECs)
2861 {
2862 Plan *plan;
2863
2864 if (IsA(bitmapqual, BitmapAndPath))
2865 {
2866 BitmapAndPath *apath = (BitmapAndPath *) bitmapqual;
2867 List *subplans = NIL;
2868 List *subquals = NIL;
2869 List *subindexquals = NIL;
2870 List *subindexECs = NIL;
2871 ListCell *l;
2872
2873 /*
2874 * There may well be redundant quals among the subplans, since a
2875 * top-level WHERE qual might have gotten used to form several
2876 * different index quals. We don't try exceedingly hard to eliminate
2877 * redundancies, but we do eliminate obvious duplicates by using
2878 * list_concat_unique.
2879 */
2880 foreach(l, apath->bitmapquals)
2881 {
2882 Plan *subplan;
2883 List *subqual;
2884 List *subindexqual;
2885 List *subindexEC;
2886
2887 subplan = create_bitmap_subplan(root, (Path *) lfirst(l),
2888 &subqual, &subindexqual,
2889 &subindexEC);
2890 subplans = lappend(subplans, subplan);
2891 subquals = list_concat_unique(subquals, subqual);
2892 subindexquals = list_concat_unique(subindexquals, subindexqual);
2893 /* Duplicates in indexECs aren't worth getting rid of */
2894 subindexECs = list_concat(subindexECs, subindexEC);
2895 }
2896 plan = (Plan *) make_bitmap_and(subplans);
2897 plan->startup_cost = apath->path.startup_cost;
2898 plan->total_cost = apath->path.total_cost;
2899 plan->plan_rows =
2900 clamp_row_est(apath->bitmapselectivity * apath->path.parent->tuples);
2901 plan->plan_width = 0; /* meaningless */
2902 plan->parallel_aware = false;
2903 plan->parallel_safe = apath->path.parallel_safe;
2904 *qual = subquals;
2905 *indexqual = subindexquals;
2906 *indexECs = subindexECs;
2907 }
2908 else if (IsA(bitmapqual, BitmapOrPath))
2909 {
2910 BitmapOrPath *opath = (BitmapOrPath *) bitmapqual;
2911 List *subplans = NIL;
2912 List *subquals = NIL;
2913 List *subindexquals = NIL;
2914 bool const_true_subqual = false;
2915 bool const_true_subindexqual = false;
2916 ListCell *l;
2917
2918 /*
2919 * Here, we only detect qual-free subplans. A qual-free subplan would
2920 * cause us to generate "... OR true ..." which we may as well reduce
2921 * to just "true". We do not try to eliminate redundant subclauses
2922 * because (a) it's not as likely as in the AND case, and (b) we might
2923 * well be working with hundreds or even thousands of OR conditions,
2924 * perhaps from a long IN list. The performance of list_append_unique
2925 * would be unacceptable.
2926 */
2927 foreach(l, opath->bitmapquals)
2928 {
2929 Plan *subplan;
2930 List *subqual;
2931 List *subindexqual;
2932 List *subindexEC;
2933
2934 subplan = create_bitmap_subplan(root, (Path *) lfirst(l),
2935 &subqual, &subindexqual,
2936 &subindexEC);
2937 subplans = lappend(subplans, subplan);
2938 if (subqual == NIL)
2939 const_true_subqual = true;
2940 else if (!const_true_subqual)
2941 subquals = lappend(subquals,
2942 make_ands_explicit(subqual));
2943 if (subindexqual == NIL)
2944 const_true_subindexqual = true;
2945 else if (!const_true_subindexqual)
2946 subindexquals = lappend(subindexquals,
2947 make_ands_explicit(subindexqual));
2948 }
2949
2950 /*
2951 * In the presence of ScalarArrayOpExpr quals, we might have built
2952 * BitmapOrPaths with just one subpath; don't add an OR step.
2953 */
2954 if (list_length(subplans) == 1)
2955 {
2956 plan = (Plan *) linitial(subplans);
2957 }
2958 else
2959 {
2960 plan = (Plan *) make_bitmap_or(subplans);
2961 plan->startup_cost = opath->path.startup_cost;
2962 plan->total_cost = opath->path.total_cost;
2963 plan->plan_rows =
2964 clamp_row_est(opath->bitmapselectivity * opath->path.parent->tuples);
2965 plan->plan_width = 0; /* meaningless */
2966 plan->parallel_aware = false;
2967 plan->parallel_safe = opath->path.parallel_safe;
2968 }
2969
2970 /*
2971 * If there were constant-TRUE subquals, the OR reduces to constant
2972 * TRUE. Also, avoid generating one-element ORs, which could happen
2973 * due to redundancy elimination or ScalarArrayOpExpr quals.
2974 */
2975 if (const_true_subqual)
2976 *qual = NIL;
2977 else if (list_length(subquals) <= 1)
2978 *qual = subquals;
2979 else
2980 *qual = list_make1(make_orclause(subquals));
2981 if (const_true_subindexqual)
2982 *indexqual = NIL;
2983 else if (list_length(subindexquals) <= 1)
2984 *indexqual = subindexquals;
2985 else
2986 *indexqual = list_make1(make_orclause(subindexquals));
2987 *indexECs = NIL;
2988 }
2989 else if (IsA(bitmapqual, IndexPath))
2990 {
2991 IndexPath *ipath = (IndexPath *) bitmapqual;
2992 IndexScan *iscan;
2993 List *subindexECs;
2994 ListCell *l;
2995
2996 /* Use the regular indexscan plan build machinery... */
2997 iscan = castNode(IndexScan,
2998 create_indexscan_plan(root, ipath,
2999 NIL, NIL, false));
3000 /* then convert to a bitmap indexscan */
3001 plan = (Plan *) make_bitmap_indexscan(iscan->scan.scanrelid,
3002 iscan->indexid,
3003 iscan->indexqual,
3004 iscan->indexqualorig);
3005 /* and set its cost/width fields appropriately */
3006 plan->startup_cost = 0.0;
3007 plan->total_cost = ipath->indextotalcost;
3008 plan->plan_rows =
3009 clamp_row_est(ipath->indexselectivity * ipath->path.parent->tuples);
3010 plan->plan_width = 0; /* meaningless */
3011 plan->parallel_aware = false;
3012 plan->parallel_safe = ipath->path.parallel_safe;
3013 *qual = get_actual_clauses(ipath->indexclauses);
3014 *indexqual = get_actual_clauses(ipath->indexquals);
3015 foreach(l, ipath->indexinfo->indpred)
3016 {
3017 Expr *pred = (Expr *) lfirst(l);
3018
3019 /*
3020 * We know that the index predicate must have been implied by the
3021 * query condition as a whole, but it may or may not be implied by
3022 * the conditions that got pushed into the bitmapqual. Avoid
3023 * generating redundant conditions.
3024 */
3025 if (!predicate_implied_by(list_make1(pred), ipath->indexclauses,
3026 false))
3027 {
3028 *qual = lappend(*qual, pred);
3029 *indexqual = lappend(*indexqual, pred);
3030 }
3031 }
3032 subindexECs = NIL;
3033 foreach(l, ipath->indexquals)
3034 {
3035 RestrictInfo *rinfo = (RestrictInfo *) lfirst(l);
3036
3037 if (rinfo->parent_ec)
3038 subindexECs = lappend(subindexECs, rinfo->parent_ec);
3039 }
3040 *indexECs = subindexECs;
3041 }
3042 else
3043 {
3044 elog(ERROR, "unrecognized node type: %d", nodeTag(bitmapqual));
3045 plan = NULL; /* keep compiler quiet */
3046 }
3047
3048 return plan;
3049 }
3050
3051 /*
3052 * create_tidscan_plan
3053 * Returns a tidscan plan for the base relation scanned by 'best_path'
3054 * with restriction clauses 'scan_clauses' and targetlist 'tlist'.
3055 */
3056 static TidScan *
create_tidscan_plan(PlannerInfo * root,TidPath * best_path,List * tlist,List * scan_clauses)3057 create_tidscan_plan(PlannerInfo *root, TidPath *best_path,
3058 List *tlist, List *scan_clauses)
3059 {
3060 TidScan *scan_plan;
3061 Index scan_relid = best_path->path.parent->relid;
3062 List *tidquals = best_path->tidquals;
3063 List *ortidquals;
3064
3065 /* it should be a base rel... */
3066 Assert(scan_relid > 0);
3067 Assert(best_path->path.parent->rtekind == RTE_RELATION);
3068
3069 /* Sort clauses into best execution order */
3070 scan_clauses = order_qual_clauses(root, scan_clauses);
3071
3072 /* Reduce RestrictInfo list to bare expressions; ignore pseudoconstants */
3073 scan_clauses = extract_actual_clauses(scan_clauses, false);
3074
3075 /* Replace any outer-relation variables with nestloop params */
3076 if (best_path->path.param_info)
3077 {
3078 tidquals = (List *)
3079 replace_nestloop_params(root, (Node *) tidquals);
3080 scan_clauses = (List *)
3081 replace_nestloop_params(root, (Node *) scan_clauses);
3082 }
3083
3084 /*
3085 * Remove any clauses that are TID quals. This is a bit tricky since the
3086 * tidquals list has implicit OR semantics.
3087 */
3088 ortidquals = tidquals;
3089 if (list_length(ortidquals) > 1)
3090 ortidquals = list_make1(make_orclause(ortidquals));
3091 scan_clauses = list_difference(scan_clauses, ortidquals);
3092
3093 scan_plan = make_tidscan(tlist,
3094 scan_clauses,
3095 scan_relid,
3096 tidquals);
3097
3098 copy_generic_path_info(&scan_plan->scan.plan, &best_path->path);
3099
3100 return scan_plan;
3101 }
3102
3103 /*
3104 * create_subqueryscan_plan
3105 * Returns a subqueryscan plan for the base relation scanned by 'best_path'
3106 * with restriction clauses 'scan_clauses' and targetlist 'tlist'.
3107 */
3108 static SubqueryScan *
create_subqueryscan_plan(PlannerInfo * root,SubqueryScanPath * best_path,List * tlist,List * scan_clauses)3109 create_subqueryscan_plan(PlannerInfo *root, SubqueryScanPath *best_path,
3110 List *tlist, List *scan_clauses)
3111 {
3112 SubqueryScan *scan_plan;
3113 RelOptInfo *rel = best_path->path.parent;
3114 Index scan_relid = rel->relid;
3115 Plan *subplan;
3116
3117 /* it should be a subquery base rel... */
3118 Assert(scan_relid > 0);
3119 Assert(rel->rtekind == RTE_SUBQUERY);
3120
3121 /*
3122 * Recursively create Plan from Path for subquery. Since we are entering
3123 * a different planner context (subroot), recurse to create_plan not
3124 * create_plan_recurse.
3125 */
3126 subplan = create_plan(rel->subroot, best_path->subpath);
3127
3128 /* Sort clauses into best execution order */
3129 scan_clauses = order_qual_clauses(root, scan_clauses);
3130
3131 /* Reduce RestrictInfo list to bare expressions; ignore pseudoconstants */
3132 scan_clauses = extract_actual_clauses(scan_clauses, false);
3133
3134 /* Replace any outer-relation variables with nestloop params */
3135 if (best_path->path.param_info)
3136 {
3137 scan_clauses = (List *)
3138 replace_nestloop_params(root, (Node *) scan_clauses);
3139 process_subquery_nestloop_params(root,
3140 rel->subplan_params);
3141 }
3142
3143 scan_plan = make_subqueryscan(tlist,
3144 scan_clauses,
3145 scan_relid,
3146 subplan);
3147
3148 copy_generic_path_info(&scan_plan->scan.plan, &best_path->path);
3149
3150 return scan_plan;
3151 }
3152
3153 /*
3154 * create_functionscan_plan
3155 * Returns a functionscan plan for the base relation scanned by 'best_path'
3156 * with restriction clauses 'scan_clauses' and targetlist 'tlist'.
3157 */
3158 static FunctionScan *
create_functionscan_plan(PlannerInfo * root,Path * best_path,List * tlist,List * scan_clauses)3159 create_functionscan_plan(PlannerInfo *root, Path *best_path,
3160 List *tlist, List *scan_clauses)
3161 {
3162 FunctionScan *scan_plan;
3163 Index scan_relid = best_path->parent->relid;
3164 RangeTblEntry *rte;
3165 List *functions;
3166
3167 /* it should be a function base rel... */
3168 Assert(scan_relid > 0);
3169 rte = planner_rt_fetch(scan_relid, root);
3170 Assert(rte->rtekind == RTE_FUNCTION);
3171 functions = rte->functions;
3172
3173 /* Sort clauses into best execution order */
3174 scan_clauses = order_qual_clauses(root, scan_clauses);
3175
3176 /* Reduce RestrictInfo list to bare expressions; ignore pseudoconstants */
3177 scan_clauses = extract_actual_clauses(scan_clauses, false);
3178
3179 /* Replace any outer-relation variables with nestloop params */
3180 if (best_path->param_info)
3181 {
3182 scan_clauses = (List *)
3183 replace_nestloop_params(root, (Node *) scan_clauses);
3184 /* The function expressions could contain nestloop params, too */
3185 functions = (List *) replace_nestloop_params(root, (Node *) functions);
3186 }
3187
3188 scan_plan = make_functionscan(tlist, scan_clauses, scan_relid,
3189 functions, rte->funcordinality);
3190
3191 copy_generic_path_info(&scan_plan->scan.plan, best_path);
3192
3193 return scan_plan;
3194 }
3195
3196 /*
3197 * create_tablefuncscan_plan
3198 * Returns a tablefuncscan plan for the base relation scanned by 'best_path'
3199 * with restriction clauses 'scan_clauses' and targetlist 'tlist'.
3200 */
3201 static TableFuncScan *
create_tablefuncscan_plan(PlannerInfo * root,Path * best_path,List * tlist,List * scan_clauses)3202 create_tablefuncscan_plan(PlannerInfo *root, Path *best_path,
3203 List *tlist, List *scan_clauses)
3204 {
3205 TableFuncScan *scan_plan;
3206 Index scan_relid = best_path->parent->relid;
3207 RangeTblEntry *rte;
3208 TableFunc *tablefunc;
3209
3210 /* it should be a function base rel... */
3211 Assert(scan_relid > 0);
3212 rte = planner_rt_fetch(scan_relid, root);
3213 Assert(rte->rtekind == RTE_TABLEFUNC);
3214 tablefunc = rte->tablefunc;
3215
3216 /* Sort clauses into best execution order */
3217 scan_clauses = order_qual_clauses(root, scan_clauses);
3218
3219 /* Reduce RestrictInfo list to bare expressions; ignore pseudoconstants */
3220 scan_clauses = extract_actual_clauses(scan_clauses, false);
3221
3222 /* Replace any outer-relation variables with nestloop params */
3223 if (best_path->param_info)
3224 {
3225 scan_clauses = (List *)
3226 replace_nestloop_params(root, (Node *) scan_clauses);
3227 /* The function expressions could contain nestloop params, too */
3228 tablefunc = (TableFunc *) replace_nestloop_params(root, (Node *) tablefunc);
3229 }
3230
3231 scan_plan = make_tablefuncscan(tlist, scan_clauses, scan_relid,
3232 tablefunc);
3233
3234 copy_generic_path_info(&scan_plan->scan.plan, best_path);
3235
3236 return scan_plan;
3237 }
3238
3239 /*
3240 * create_valuesscan_plan
3241 * Returns a valuesscan plan for the base relation scanned by 'best_path'
3242 * with restriction clauses 'scan_clauses' and targetlist 'tlist'.
3243 */
3244 static ValuesScan *
create_valuesscan_plan(PlannerInfo * root,Path * best_path,List * tlist,List * scan_clauses)3245 create_valuesscan_plan(PlannerInfo *root, Path *best_path,
3246 List *tlist, List *scan_clauses)
3247 {
3248 ValuesScan *scan_plan;
3249 Index scan_relid = best_path->parent->relid;
3250 RangeTblEntry *rte;
3251 List *values_lists;
3252
3253 /* it should be a values base rel... */
3254 Assert(scan_relid > 0);
3255 rte = planner_rt_fetch(scan_relid, root);
3256 Assert(rte->rtekind == RTE_VALUES);
3257 values_lists = rte->values_lists;
3258
3259 /* Sort clauses into best execution order */
3260 scan_clauses = order_qual_clauses(root, scan_clauses);
3261
3262 /* Reduce RestrictInfo list to bare expressions; ignore pseudoconstants */
3263 scan_clauses = extract_actual_clauses(scan_clauses, false);
3264
3265 /* Replace any outer-relation variables with nestloop params */
3266 if (best_path->param_info)
3267 {
3268 scan_clauses = (List *)
3269 replace_nestloop_params(root, (Node *) scan_clauses);
3270 /* The values lists could contain nestloop params, too */
3271 values_lists = (List *)
3272 replace_nestloop_params(root, (Node *) values_lists);
3273 }
3274
3275 scan_plan = make_valuesscan(tlist, scan_clauses, scan_relid,
3276 values_lists);
3277
3278 copy_generic_path_info(&scan_plan->scan.plan, best_path);
3279
3280 return scan_plan;
3281 }
3282
3283 /*
3284 * create_ctescan_plan
3285 * Returns a ctescan plan for the base relation scanned by 'best_path'
3286 * with restriction clauses 'scan_clauses' and targetlist 'tlist'.
3287 */
3288 static CteScan *
create_ctescan_plan(PlannerInfo * root,Path * best_path,List * tlist,List * scan_clauses)3289 create_ctescan_plan(PlannerInfo *root, Path *best_path,
3290 List *tlist, List *scan_clauses)
3291 {
3292 CteScan *scan_plan;
3293 Index scan_relid = best_path->parent->relid;
3294 RangeTblEntry *rte;
3295 SubPlan *ctesplan = NULL;
3296 int plan_id;
3297 int cte_param_id;
3298 PlannerInfo *cteroot;
3299 Index levelsup;
3300 int ndx;
3301 ListCell *lc;
3302
3303 Assert(scan_relid > 0);
3304 rte = planner_rt_fetch(scan_relid, root);
3305 Assert(rte->rtekind == RTE_CTE);
3306 Assert(!rte->self_reference);
3307
3308 /*
3309 * Find the referenced CTE, and locate the SubPlan previously made for it.
3310 */
3311 levelsup = rte->ctelevelsup;
3312 cteroot = root;
3313 while (levelsup-- > 0)
3314 {
3315 cteroot = cteroot->parent_root;
3316 if (!cteroot) /* shouldn't happen */
3317 elog(ERROR, "bad levelsup for CTE \"%s\"", rte->ctename);
3318 }
3319
3320 /*
3321 * Note: cte_plan_ids can be shorter than cteList, if we are still working
3322 * on planning the CTEs (ie, this is a side-reference from another CTE).
3323 * So we mustn't use forboth here.
3324 */
3325 ndx = 0;
3326 foreach(lc, cteroot->parse->cteList)
3327 {
3328 CommonTableExpr *cte = (CommonTableExpr *) lfirst(lc);
3329
3330 if (strcmp(cte->ctename, rte->ctename) == 0)
3331 break;
3332 ndx++;
3333 }
3334 if (lc == NULL) /* shouldn't happen */
3335 elog(ERROR, "could not find CTE \"%s\"", rte->ctename);
3336 if (ndx >= list_length(cteroot->cte_plan_ids))
3337 elog(ERROR, "could not find plan for CTE \"%s\"", rte->ctename);
3338 plan_id = list_nth_int(cteroot->cte_plan_ids, ndx);
3339 Assert(plan_id > 0);
3340 foreach(lc, cteroot->init_plans)
3341 {
3342 ctesplan = (SubPlan *) lfirst(lc);
3343 if (ctesplan->plan_id == plan_id)
3344 break;
3345 }
3346 if (lc == NULL) /* shouldn't happen */
3347 elog(ERROR, "could not find plan for CTE \"%s\"", rte->ctename);
3348
3349 /*
3350 * We need the CTE param ID, which is the sole member of the SubPlan's
3351 * setParam list.
3352 */
3353 cte_param_id = linitial_int(ctesplan->setParam);
3354
3355 /* Sort clauses into best execution order */
3356 scan_clauses = order_qual_clauses(root, scan_clauses);
3357
3358 /* Reduce RestrictInfo list to bare expressions; ignore pseudoconstants */
3359 scan_clauses = extract_actual_clauses(scan_clauses, false);
3360
3361 /* Replace any outer-relation variables with nestloop params */
3362 if (best_path->param_info)
3363 {
3364 scan_clauses = (List *)
3365 replace_nestloop_params(root, (Node *) scan_clauses);
3366 }
3367
3368 scan_plan = make_ctescan(tlist, scan_clauses, scan_relid,
3369 plan_id, cte_param_id);
3370
3371 copy_generic_path_info(&scan_plan->scan.plan, best_path);
3372
3373 return scan_plan;
3374 }
3375
3376 /*
3377 * create_namedtuplestorescan_plan
3378 * Returns a tuplestorescan plan for the base relation scanned by
3379 * 'best_path' with restriction clauses 'scan_clauses' and targetlist
3380 * 'tlist'.
3381 */
3382 static NamedTuplestoreScan *
create_namedtuplestorescan_plan(PlannerInfo * root,Path * best_path,List * tlist,List * scan_clauses)3383 create_namedtuplestorescan_plan(PlannerInfo *root, Path *best_path,
3384 List *tlist, List *scan_clauses)
3385 {
3386 NamedTuplestoreScan *scan_plan;
3387 Index scan_relid = best_path->parent->relid;
3388 RangeTblEntry *rte;
3389
3390 Assert(scan_relid > 0);
3391 rte = planner_rt_fetch(scan_relid, root);
3392 Assert(rte->rtekind == RTE_NAMEDTUPLESTORE);
3393
3394 /* Sort clauses into best execution order */
3395 scan_clauses = order_qual_clauses(root, scan_clauses);
3396
3397 /* Reduce RestrictInfo list to bare expressions; ignore pseudoconstants */
3398 scan_clauses = extract_actual_clauses(scan_clauses, false);
3399
3400 /* Replace any outer-relation variables with nestloop params */
3401 if (best_path->param_info)
3402 {
3403 scan_clauses = (List *)
3404 replace_nestloop_params(root, (Node *) scan_clauses);
3405 }
3406
3407 scan_plan = make_namedtuplestorescan(tlist, scan_clauses, scan_relid,
3408 rte->enrname);
3409
3410 copy_generic_path_info(&scan_plan->scan.plan, best_path);
3411
3412 return scan_plan;
3413 }
3414
3415 /*
3416 * create_worktablescan_plan
3417 * Returns a worktablescan plan for the base relation scanned by 'best_path'
3418 * with restriction clauses 'scan_clauses' and targetlist 'tlist'.
3419 */
3420 static WorkTableScan *
create_worktablescan_plan(PlannerInfo * root,Path * best_path,List * tlist,List * scan_clauses)3421 create_worktablescan_plan(PlannerInfo *root, Path *best_path,
3422 List *tlist, List *scan_clauses)
3423 {
3424 WorkTableScan *scan_plan;
3425 Index scan_relid = best_path->parent->relid;
3426 RangeTblEntry *rte;
3427 Index levelsup;
3428 PlannerInfo *cteroot;
3429
3430 Assert(scan_relid > 0);
3431 rte = planner_rt_fetch(scan_relid, root);
3432 Assert(rte->rtekind == RTE_CTE);
3433 Assert(rte->self_reference);
3434
3435 /*
3436 * We need to find the worktable param ID, which is in the plan level
3437 * that's processing the recursive UNION, which is one level *below* where
3438 * the CTE comes from.
3439 */
3440 levelsup = rte->ctelevelsup;
3441 if (levelsup == 0) /* shouldn't happen */
3442 elog(ERROR, "bad levelsup for CTE \"%s\"", rte->ctename);
3443 levelsup--;
3444 cteroot = root;
3445 while (levelsup-- > 0)
3446 {
3447 cteroot = cteroot->parent_root;
3448 if (!cteroot) /* shouldn't happen */
3449 elog(ERROR, "bad levelsup for CTE \"%s\"", rte->ctename);
3450 }
3451 if (cteroot->wt_param_id < 0) /* shouldn't happen */
3452 elog(ERROR, "could not find param ID for CTE \"%s\"", rte->ctename);
3453
3454 /* Sort clauses into best execution order */
3455 scan_clauses = order_qual_clauses(root, scan_clauses);
3456
3457 /* Reduce RestrictInfo list to bare expressions; ignore pseudoconstants */
3458 scan_clauses = extract_actual_clauses(scan_clauses, false);
3459
3460 /* Replace any outer-relation variables with nestloop params */
3461 if (best_path->param_info)
3462 {
3463 scan_clauses = (List *)
3464 replace_nestloop_params(root, (Node *) scan_clauses);
3465 }
3466
3467 scan_plan = make_worktablescan(tlist, scan_clauses, scan_relid,
3468 cteroot->wt_param_id);
3469
3470 copy_generic_path_info(&scan_plan->scan.plan, best_path);
3471
3472 return scan_plan;
3473 }
3474
3475 /*
3476 * create_foreignscan_plan
3477 * Returns a foreignscan plan for the relation scanned by 'best_path'
3478 * with restriction clauses 'scan_clauses' and targetlist 'tlist'.
3479 */
3480 static ForeignScan *
create_foreignscan_plan(PlannerInfo * root,ForeignPath * best_path,List * tlist,List * scan_clauses)3481 create_foreignscan_plan(PlannerInfo *root, ForeignPath *best_path,
3482 List *tlist, List *scan_clauses)
3483 {
3484 ForeignScan *scan_plan;
3485 RelOptInfo *rel = best_path->path.parent;
3486 Index scan_relid = rel->relid;
3487 Oid rel_oid = InvalidOid;
3488 Plan *outer_plan = NULL;
3489
3490 Assert(rel->fdwroutine != NULL);
3491
3492 /* transform the child path if any */
3493 if (best_path->fdw_outerpath)
3494 outer_plan = create_plan_recurse(root, best_path->fdw_outerpath,
3495 CP_EXACT_TLIST);
3496
3497 /*
3498 * If we're scanning a base relation, fetch its OID. (Irrelevant if
3499 * scanning a join relation.)
3500 */
3501 if (scan_relid > 0)
3502 {
3503 RangeTblEntry *rte;
3504
3505 Assert(rel->rtekind == RTE_RELATION);
3506 rte = planner_rt_fetch(scan_relid, root);
3507 Assert(rte->rtekind == RTE_RELATION);
3508 rel_oid = rte->relid;
3509 }
3510
3511 /*
3512 * Sort clauses into best execution order. We do this first since the FDW
3513 * might have more info than we do and wish to adjust the ordering.
3514 */
3515 scan_clauses = order_qual_clauses(root, scan_clauses);
3516
3517 /*
3518 * Let the FDW perform its processing on the restriction clauses and
3519 * generate the plan node. Note that the FDW might remove restriction
3520 * clauses that it intends to execute remotely, or even add more (if it
3521 * has selected some join clauses for remote use but also wants them
3522 * rechecked locally).
3523 */
3524 scan_plan = rel->fdwroutine->GetForeignPlan(root, rel, rel_oid,
3525 best_path,
3526 tlist, scan_clauses,
3527 outer_plan);
3528
3529 /* Copy cost data from Path to Plan; no need to make FDW do this */
3530 copy_generic_path_info(&scan_plan->scan.plan, &best_path->path);
3531
3532 /* Copy foreign server OID; likewise, no need to make FDW do this */
3533 scan_plan->fs_server = rel->serverid;
3534
3535 /*
3536 * Likewise, copy the relids that are represented by this foreign scan. An
3537 * upper rel doesn't have relids set, but it covers all the base relations
3538 * participating in the underlying scan, so use root's all_baserels.
3539 */
3540 if (IS_UPPER_REL(rel))
3541 scan_plan->fs_relids = root->all_baserels;
3542 else
3543 scan_plan->fs_relids = best_path->path.parent->relids;
3544
3545 /*
3546 * If this is a foreign join, and to make it valid to push down we had to
3547 * assume that the current user is the same as some user explicitly named
3548 * in the query, mark the finished plan as depending on the current user.
3549 */
3550 if (rel->useridiscurrent)
3551 root->glob->dependsOnRole = true;
3552
3553 /*
3554 * Replace any outer-relation variables with nestloop params in the qual,
3555 * fdw_exprs and fdw_recheck_quals expressions. We do this last so that
3556 * the FDW doesn't have to be involved. (Note that parts of fdw_exprs or
3557 * fdw_recheck_quals could have come from join clauses, so doing this
3558 * beforehand on the scan_clauses wouldn't work.) We assume
3559 * fdw_scan_tlist contains no such variables.
3560 */
3561 if (best_path->path.param_info)
3562 {
3563 scan_plan->scan.plan.qual = (List *)
3564 replace_nestloop_params(root, (Node *) scan_plan->scan.plan.qual);
3565 scan_plan->fdw_exprs = (List *)
3566 replace_nestloop_params(root, (Node *) scan_plan->fdw_exprs);
3567 scan_plan->fdw_recheck_quals = (List *)
3568 replace_nestloop_params(root,
3569 (Node *) scan_plan->fdw_recheck_quals);
3570 }
3571
3572 /*
3573 * If rel is a base relation, detect whether any system columns are
3574 * requested from the rel. (If rel is a join relation, rel->relid will be
3575 * 0, but there can be no Var with relid 0 in the rel's targetlist or the
3576 * restriction clauses, so we skip this in that case. Note that any such
3577 * columns in base relations that were joined are assumed to be contained
3578 * in fdw_scan_tlist.) This is a bit of a kluge and might go away
3579 * someday, so we intentionally leave it out of the API presented to FDWs.
3580 */
3581 scan_plan->fsSystemCol = false;
3582 if (scan_relid > 0)
3583 {
3584 Bitmapset *attrs_used = NULL;
3585 ListCell *lc;
3586 int i;
3587
3588 /*
3589 * First, examine all the attributes needed for joins or final output.
3590 * Note: we must look at rel's targetlist, not the attr_needed data,
3591 * because attr_needed isn't computed for inheritance child rels.
3592 */
3593 pull_varattnos((Node *) rel->reltarget->exprs, scan_relid, &attrs_used);
3594
3595 /* Add all the attributes used by restriction clauses. */
3596 foreach(lc, rel->baserestrictinfo)
3597 {
3598 RestrictInfo *rinfo = (RestrictInfo *) lfirst(lc);
3599
3600 pull_varattnos((Node *) rinfo->clause, scan_relid, &attrs_used);
3601 }
3602
3603 /* Now, are any system columns requested from rel? */
3604 for (i = FirstLowInvalidHeapAttributeNumber + 1; i < 0; i++)
3605 {
3606 if (bms_is_member(i - FirstLowInvalidHeapAttributeNumber, attrs_used))
3607 {
3608 scan_plan->fsSystemCol = true;
3609 break;
3610 }
3611 }
3612
3613 bms_free(attrs_used);
3614 }
3615
3616 return scan_plan;
3617 }
3618
3619 /*
3620 * create_custom_plan
3621 *
3622 * Transform a CustomPath into a Plan.
3623 */
3624 static CustomScan *
create_customscan_plan(PlannerInfo * root,CustomPath * best_path,List * tlist,List * scan_clauses)3625 create_customscan_plan(PlannerInfo *root, CustomPath *best_path,
3626 List *tlist, List *scan_clauses)
3627 {
3628 CustomScan *cplan;
3629 RelOptInfo *rel = best_path->path.parent;
3630 List *custom_plans = NIL;
3631 ListCell *lc;
3632
3633 /* Recursively transform child paths. */
3634 foreach(lc, best_path->custom_paths)
3635 {
3636 Plan *plan = create_plan_recurse(root, (Path *) lfirst(lc),
3637 CP_EXACT_TLIST);
3638
3639 custom_plans = lappend(custom_plans, plan);
3640 }
3641
3642 /*
3643 * Sort clauses into the best execution order, although custom-scan
3644 * provider can reorder them again.
3645 */
3646 scan_clauses = order_qual_clauses(root, scan_clauses);
3647
3648 /*
3649 * Invoke custom plan provider to create the Plan node represented by the
3650 * CustomPath.
3651 */
3652 cplan = castNode(CustomScan,
3653 best_path->methods->PlanCustomPath(root,
3654 rel,
3655 best_path,
3656 tlist,
3657 scan_clauses,
3658 custom_plans));
3659
3660 /*
3661 * Copy cost data from Path to Plan; no need to make custom-plan providers
3662 * do this
3663 */
3664 copy_generic_path_info(&cplan->scan.plan, &best_path->path);
3665
3666 /* Likewise, copy the relids that are represented by this custom scan */
3667 cplan->custom_relids = best_path->path.parent->relids;
3668
3669 /*
3670 * Replace any outer-relation variables with nestloop params in the qual
3671 * and custom_exprs expressions. We do this last so that the custom-plan
3672 * provider doesn't have to be involved. (Note that parts of custom_exprs
3673 * could have come from join clauses, so doing this beforehand on the
3674 * scan_clauses wouldn't work.) We assume custom_scan_tlist contains no
3675 * such variables.
3676 */
3677 if (best_path->path.param_info)
3678 {
3679 cplan->scan.plan.qual = (List *)
3680 replace_nestloop_params(root, (Node *) cplan->scan.plan.qual);
3681 cplan->custom_exprs = (List *)
3682 replace_nestloop_params(root, (Node *) cplan->custom_exprs);
3683 }
3684
3685 return cplan;
3686 }
3687
3688
3689 /*****************************************************************************
3690 *
3691 * JOIN METHODS
3692 *
3693 *****************************************************************************/
3694
3695 static NestLoop *
create_nestloop_plan(PlannerInfo * root,NestPath * best_path)3696 create_nestloop_plan(PlannerInfo *root,
3697 NestPath *best_path)
3698 {
3699 NestLoop *join_plan;
3700 Plan *outer_plan;
3701 Plan *inner_plan;
3702 List *tlist = build_path_tlist(root, &best_path->path);
3703 List *joinrestrictclauses = best_path->joinrestrictinfo;
3704 List *joinclauses;
3705 List *otherclauses;
3706 Relids outerrelids;
3707 List *nestParams;
3708 Relids saveOuterRels = root->curOuterRels;
3709
3710 /* NestLoop can project, so no need to be picky about child tlists */
3711 outer_plan = create_plan_recurse(root, best_path->outerjoinpath, 0);
3712
3713 /* For a nestloop, include outer relids in curOuterRels for inner side */
3714 root->curOuterRels = bms_union(root->curOuterRels,
3715 best_path->outerjoinpath->parent->relids);
3716
3717 inner_plan = create_plan_recurse(root, best_path->innerjoinpath, 0);
3718
3719 /* Restore curOuterRels */
3720 bms_free(root->curOuterRels);
3721 root->curOuterRels = saveOuterRels;
3722
3723 /* Sort join qual clauses into best execution order */
3724 joinrestrictclauses = order_qual_clauses(root, joinrestrictclauses);
3725
3726 /* Get the join qual clauses (in plain expression form) */
3727 /* Any pseudoconstant clauses are ignored here */
3728 if (IS_OUTER_JOIN(best_path->jointype))
3729 {
3730 extract_actual_join_clauses(joinrestrictclauses,
3731 best_path->path.parent->relids,
3732 &joinclauses, &otherclauses);
3733 }
3734 else
3735 {
3736 /* We can treat all clauses alike for an inner join */
3737 joinclauses = extract_actual_clauses(joinrestrictclauses, false);
3738 otherclauses = NIL;
3739 }
3740
3741 /* Replace any outer-relation variables with nestloop params */
3742 if (best_path->path.param_info)
3743 {
3744 joinclauses = (List *)
3745 replace_nestloop_params(root, (Node *) joinclauses);
3746 otherclauses = (List *)
3747 replace_nestloop_params(root, (Node *) otherclauses);
3748 }
3749
3750 /*
3751 * Identify any nestloop parameters that should be supplied by this join
3752 * node, and remove them from root->curOuterParams.
3753 */
3754 outerrelids = best_path->outerjoinpath->parent->relids;
3755 nestParams = identify_current_nestloop_params(root, outerrelids);
3756
3757 join_plan = make_nestloop(tlist,
3758 joinclauses,
3759 otherclauses,
3760 nestParams,
3761 outer_plan,
3762 inner_plan,
3763 best_path->jointype,
3764 best_path->inner_unique);
3765
3766 copy_generic_path_info(&join_plan->join.plan, &best_path->path);
3767
3768 return join_plan;
3769 }
3770
3771 static MergeJoin *
create_mergejoin_plan(PlannerInfo * root,MergePath * best_path)3772 create_mergejoin_plan(PlannerInfo *root,
3773 MergePath *best_path)
3774 {
3775 MergeJoin *join_plan;
3776 Plan *outer_plan;
3777 Plan *inner_plan;
3778 List *tlist = build_path_tlist(root, &best_path->jpath.path);
3779 List *joinclauses;
3780 List *otherclauses;
3781 List *mergeclauses;
3782 List *outerpathkeys;
3783 List *innerpathkeys;
3784 int nClauses;
3785 Oid *mergefamilies;
3786 Oid *mergecollations;
3787 int *mergestrategies;
3788 bool *mergenullsfirst;
3789 PathKey *opathkey;
3790 EquivalenceClass *opeclass;
3791 int i;
3792 ListCell *lc;
3793 ListCell *lop;
3794 ListCell *lip;
3795
3796 /*
3797 * MergeJoin can project, so we don't have to demand exact tlists from the
3798 * inputs. However, if we're intending to sort an input's result, it's
3799 * best to request a small tlist so we aren't sorting more data than
3800 * necessary.
3801 */
3802 outer_plan = create_plan_recurse(root, best_path->jpath.outerjoinpath,
3803 (best_path->outersortkeys != NIL) ? CP_SMALL_TLIST : 0);
3804
3805 inner_plan = create_plan_recurse(root, best_path->jpath.innerjoinpath,
3806 (best_path->innersortkeys != NIL) ? CP_SMALL_TLIST : 0);
3807
3808 /* Sort join qual clauses into best execution order */
3809 /* NB: do NOT reorder the mergeclauses */
3810 joinclauses = order_qual_clauses(root, best_path->jpath.joinrestrictinfo);
3811
3812 /* Get the join qual clauses (in plain expression form) */
3813 /* Any pseudoconstant clauses are ignored here */
3814 if (IS_OUTER_JOIN(best_path->jpath.jointype))
3815 {
3816 extract_actual_join_clauses(joinclauses,
3817 best_path->jpath.path.parent->relids,
3818 &joinclauses, &otherclauses);
3819 }
3820 else
3821 {
3822 /* We can treat all clauses alike for an inner join */
3823 joinclauses = extract_actual_clauses(joinclauses, false);
3824 otherclauses = NIL;
3825 }
3826
3827 /*
3828 * Remove the mergeclauses from the list of join qual clauses, leaving the
3829 * list of quals that must be checked as qpquals.
3830 */
3831 mergeclauses = get_actual_clauses(best_path->path_mergeclauses);
3832 joinclauses = list_difference(joinclauses, mergeclauses);
3833
3834 /*
3835 * Replace any outer-relation variables with nestloop params. There
3836 * should not be any in the mergeclauses.
3837 */
3838 if (best_path->jpath.path.param_info)
3839 {
3840 joinclauses = (List *)
3841 replace_nestloop_params(root, (Node *) joinclauses);
3842 otherclauses = (List *)
3843 replace_nestloop_params(root, (Node *) otherclauses);
3844 }
3845
3846 /*
3847 * Rearrange mergeclauses, if needed, so that the outer variable is always
3848 * on the left; mark the mergeclause restrictinfos with correct
3849 * outer_is_left status.
3850 */
3851 mergeclauses = get_switched_clauses(best_path->path_mergeclauses,
3852 best_path->jpath.outerjoinpath->parent->relids);
3853
3854 /*
3855 * Create explicit sort nodes for the outer and inner paths if necessary.
3856 */
3857 if (best_path->outersortkeys)
3858 {
3859 Sort *sort = make_sort_from_pathkeys(outer_plan,
3860 best_path->outersortkeys);
3861
3862 label_sort_with_costsize(root, sort, -1.0);
3863 outer_plan = (Plan *) sort;
3864 outerpathkeys = best_path->outersortkeys;
3865 }
3866 else
3867 outerpathkeys = best_path->jpath.outerjoinpath->pathkeys;
3868
3869 if (best_path->innersortkeys)
3870 {
3871 Sort *sort = make_sort_from_pathkeys(inner_plan,
3872 best_path->innersortkeys);
3873
3874 label_sort_with_costsize(root, sort, -1.0);
3875 inner_plan = (Plan *) sort;
3876 innerpathkeys = best_path->innersortkeys;
3877 }
3878 else
3879 innerpathkeys = best_path->jpath.innerjoinpath->pathkeys;
3880
3881 /*
3882 * If specified, add a materialize node to shield the inner plan from the
3883 * need to handle mark/restore.
3884 */
3885 if (best_path->materialize_inner)
3886 {
3887 Plan *matplan = (Plan *) make_material(inner_plan);
3888
3889 /*
3890 * We assume the materialize will not spill to disk, and therefore
3891 * charge just cpu_operator_cost per tuple. (Keep this estimate in
3892 * sync with final_cost_mergejoin.)
3893 */
3894 copy_plan_costsize(matplan, inner_plan);
3895 matplan->total_cost += cpu_operator_cost * matplan->plan_rows;
3896
3897 inner_plan = matplan;
3898 }
3899
3900 /*
3901 * Compute the opfamily/collation/strategy/nullsfirst arrays needed by the
3902 * executor. The information is in the pathkeys for the two inputs, but
3903 * we need to be careful about the possibility of mergeclauses sharing a
3904 * pathkey, as well as the possibility that the inner pathkeys are not in
3905 * an order matching the mergeclauses.
3906 */
3907 nClauses = list_length(mergeclauses);
3908 Assert(nClauses == list_length(best_path->path_mergeclauses));
3909 mergefamilies = (Oid *) palloc(nClauses * sizeof(Oid));
3910 mergecollations = (Oid *) palloc(nClauses * sizeof(Oid));
3911 mergestrategies = (int *) palloc(nClauses * sizeof(int));
3912 mergenullsfirst = (bool *) palloc(nClauses * sizeof(bool));
3913
3914 opathkey = NULL;
3915 opeclass = NULL;
3916 lop = list_head(outerpathkeys);
3917 lip = list_head(innerpathkeys);
3918 i = 0;
3919 foreach(lc, best_path->path_mergeclauses)
3920 {
3921 RestrictInfo *rinfo = lfirst_node(RestrictInfo, lc);
3922 EquivalenceClass *oeclass;
3923 EquivalenceClass *ieclass;
3924 PathKey *ipathkey = NULL;
3925 EquivalenceClass *ipeclass = NULL;
3926 bool first_inner_match = false;
3927
3928 /* fetch outer/inner eclass from mergeclause */
3929 if (rinfo->outer_is_left)
3930 {
3931 oeclass = rinfo->left_ec;
3932 ieclass = rinfo->right_ec;
3933 }
3934 else
3935 {
3936 oeclass = rinfo->right_ec;
3937 ieclass = rinfo->left_ec;
3938 }
3939 Assert(oeclass != NULL);
3940 Assert(ieclass != NULL);
3941
3942 /*
3943 * We must identify the pathkey elements associated with this clause
3944 * by matching the eclasses (which should give a unique match, since
3945 * the pathkey lists should be canonical). In typical cases the merge
3946 * clauses are one-to-one with the pathkeys, but when dealing with
3947 * partially redundant query conditions, things are more complicated.
3948 *
3949 * lop and lip reference the first as-yet-unmatched pathkey elements.
3950 * If they're NULL then all pathkey elements have been matched.
3951 *
3952 * The ordering of the outer pathkeys should match the mergeclauses,
3953 * by construction (see find_mergeclauses_for_outer_pathkeys()). There
3954 * could be more than one mergeclause for the same outer pathkey, but
3955 * no pathkey may be entirely skipped over.
3956 */
3957 if (oeclass != opeclass) /* multiple matches are not interesting */
3958 {
3959 /* doesn't match the current opathkey, so must match the next */
3960 if (lop == NULL)
3961 elog(ERROR, "outer pathkeys do not match mergeclauses");
3962 opathkey = (PathKey *) lfirst(lop);
3963 opeclass = opathkey->pk_eclass;
3964 lop = lnext(lop);
3965 if (oeclass != opeclass)
3966 elog(ERROR, "outer pathkeys do not match mergeclauses");
3967 }
3968
3969 /*
3970 * The inner pathkeys likewise should not have skipped-over keys, but
3971 * it's possible for a mergeclause to reference some earlier inner
3972 * pathkey if we had redundant pathkeys. For example we might have
3973 * mergeclauses like "o.a = i.x AND o.b = i.y AND o.c = i.x". The
3974 * implied inner ordering is then "ORDER BY x, y, x", but the pathkey
3975 * mechanism drops the second sort by x as redundant, and this code
3976 * must cope.
3977 *
3978 * It's also possible for the implied inner-rel ordering to be like
3979 * "ORDER BY x, y, x DESC". We still drop the second instance of x as
3980 * redundant; but this means that the sort ordering of a redundant
3981 * inner pathkey should not be considered significant. So we must
3982 * detect whether this is the first clause matching an inner pathkey.
3983 */
3984 if (lip)
3985 {
3986 ipathkey = (PathKey *) lfirst(lip);
3987 ipeclass = ipathkey->pk_eclass;
3988 if (ieclass == ipeclass)
3989 {
3990 /* successful first match to this inner pathkey */
3991 lip = lnext(lip);
3992 first_inner_match = true;
3993 }
3994 }
3995 if (!first_inner_match)
3996 {
3997 /* redundant clause ... must match something before lip */
3998 ListCell *l2;
3999
4000 foreach(l2, innerpathkeys)
4001 {
4002 if (l2 == lip)
4003 break;
4004 ipathkey = (PathKey *) lfirst(l2);
4005 ipeclass = ipathkey->pk_eclass;
4006 if (ieclass == ipeclass)
4007 break;
4008 }
4009 if (ieclass != ipeclass)
4010 elog(ERROR, "inner pathkeys do not match mergeclauses");
4011 }
4012
4013 /*
4014 * The pathkeys should always match each other as to opfamily and
4015 * collation (which affect equality), but if we're considering a
4016 * redundant inner pathkey, its sort ordering might not match. In
4017 * such cases we may ignore the inner pathkey's sort ordering and use
4018 * the outer's. (In effect, we're lying to the executor about the
4019 * sort direction of this inner column, but it does not matter since
4020 * the run-time row comparisons would only reach this column when
4021 * there's equality for the earlier column containing the same eclass.
4022 * There could be only one value in this column for the range of inner
4023 * rows having a given value in the earlier column, so it does not
4024 * matter which way we imagine this column to be ordered.) But a
4025 * non-redundant inner pathkey had better match outer's ordering too.
4026 */
4027 if (opathkey->pk_opfamily != ipathkey->pk_opfamily ||
4028 opathkey->pk_eclass->ec_collation != ipathkey->pk_eclass->ec_collation)
4029 elog(ERROR, "left and right pathkeys do not match in mergejoin");
4030 if (first_inner_match &&
4031 (opathkey->pk_strategy != ipathkey->pk_strategy ||
4032 opathkey->pk_nulls_first != ipathkey->pk_nulls_first))
4033 elog(ERROR, "left and right pathkeys do not match in mergejoin");
4034
4035 /* OK, save info for executor */
4036 mergefamilies[i] = opathkey->pk_opfamily;
4037 mergecollations[i] = opathkey->pk_eclass->ec_collation;
4038 mergestrategies[i] = opathkey->pk_strategy;
4039 mergenullsfirst[i] = opathkey->pk_nulls_first;
4040 i++;
4041 }
4042
4043 /*
4044 * Note: it is not an error if we have additional pathkey elements (i.e.,
4045 * lop or lip isn't NULL here). The input paths might be better-sorted
4046 * than we need for the current mergejoin.
4047 */
4048
4049 /*
4050 * Now we can build the mergejoin node.
4051 */
4052 join_plan = make_mergejoin(tlist,
4053 joinclauses,
4054 otherclauses,
4055 mergeclauses,
4056 mergefamilies,
4057 mergecollations,
4058 mergestrategies,
4059 mergenullsfirst,
4060 outer_plan,
4061 inner_plan,
4062 best_path->jpath.jointype,
4063 best_path->jpath.inner_unique,
4064 best_path->skip_mark_restore);
4065
4066 /* Costs of sort and material steps are included in path cost already */
4067 copy_generic_path_info(&join_plan->join.plan, &best_path->jpath.path);
4068
4069 return join_plan;
4070 }
4071
4072 static HashJoin *
create_hashjoin_plan(PlannerInfo * root,HashPath * best_path)4073 create_hashjoin_plan(PlannerInfo *root,
4074 HashPath *best_path)
4075 {
4076 HashJoin *join_plan;
4077 Hash *hash_plan;
4078 Plan *outer_plan;
4079 Plan *inner_plan;
4080 List *tlist = build_path_tlist(root, &best_path->jpath.path);
4081 List *joinclauses;
4082 List *otherclauses;
4083 List *hashclauses;
4084 Oid skewTable = InvalidOid;
4085 AttrNumber skewColumn = InvalidAttrNumber;
4086 bool skewInherit = false;
4087
4088 /*
4089 * HashJoin can project, so we don't have to demand exact tlists from the
4090 * inputs. However, it's best to request a small tlist from the inner
4091 * side, so that we aren't storing more data than necessary. Likewise, if
4092 * we anticipate batching, request a small tlist from the outer side so
4093 * that we don't put extra data in the outer batch files.
4094 */
4095 outer_plan = create_plan_recurse(root, best_path->jpath.outerjoinpath,
4096 (best_path->num_batches > 1) ? CP_SMALL_TLIST : 0);
4097
4098 inner_plan = create_plan_recurse(root, best_path->jpath.innerjoinpath,
4099 CP_SMALL_TLIST);
4100
4101 /* Sort join qual clauses into best execution order */
4102 joinclauses = order_qual_clauses(root, best_path->jpath.joinrestrictinfo);
4103 /* There's no point in sorting the hash clauses ... */
4104
4105 /* Get the join qual clauses (in plain expression form) */
4106 /* Any pseudoconstant clauses are ignored here */
4107 if (IS_OUTER_JOIN(best_path->jpath.jointype))
4108 {
4109 extract_actual_join_clauses(joinclauses,
4110 best_path->jpath.path.parent->relids,
4111 &joinclauses, &otherclauses);
4112 }
4113 else
4114 {
4115 /* We can treat all clauses alike for an inner join */
4116 joinclauses = extract_actual_clauses(joinclauses, false);
4117 otherclauses = NIL;
4118 }
4119
4120 /*
4121 * Remove the hashclauses from the list of join qual clauses, leaving the
4122 * list of quals that must be checked as qpquals.
4123 */
4124 hashclauses = get_actual_clauses(best_path->path_hashclauses);
4125 joinclauses = list_difference(joinclauses, hashclauses);
4126
4127 /*
4128 * Replace any outer-relation variables with nestloop params. There
4129 * should not be any in the hashclauses.
4130 */
4131 if (best_path->jpath.path.param_info)
4132 {
4133 joinclauses = (List *)
4134 replace_nestloop_params(root, (Node *) joinclauses);
4135 otherclauses = (List *)
4136 replace_nestloop_params(root, (Node *) otherclauses);
4137 }
4138
4139 /*
4140 * Rearrange hashclauses, if needed, so that the outer variable is always
4141 * on the left.
4142 */
4143 hashclauses = get_switched_clauses(best_path->path_hashclauses,
4144 best_path->jpath.outerjoinpath->parent->relids);
4145
4146 /*
4147 * If there is a single join clause and we can identify the outer variable
4148 * as a simple column reference, supply its identity for possible use in
4149 * skew optimization. (Note: in principle we could do skew optimization
4150 * with multiple join clauses, but we'd have to be able to determine the
4151 * most common combinations of outer values, which we don't currently have
4152 * enough stats for.)
4153 */
4154 if (list_length(hashclauses) == 1)
4155 {
4156 OpExpr *clause = (OpExpr *) linitial(hashclauses);
4157 Node *node;
4158
4159 Assert(is_opclause(clause));
4160 node = (Node *) linitial(clause->args);
4161 if (IsA(node, RelabelType))
4162 node = (Node *) ((RelabelType *) node)->arg;
4163 if (IsA(node, Var))
4164 {
4165 Var *var = (Var *) node;
4166 RangeTblEntry *rte;
4167
4168 rte = root->simple_rte_array[var->varno];
4169 if (rte->rtekind == RTE_RELATION)
4170 {
4171 skewTable = rte->relid;
4172 skewColumn = var->varattno;
4173 skewInherit = rte->inh;
4174 }
4175 }
4176 }
4177
4178 /*
4179 * Build the hash node and hash join node.
4180 */
4181 hash_plan = make_hash(inner_plan,
4182 skewTable,
4183 skewColumn,
4184 skewInherit);
4185
4186 /*
4187 * Set Hash node's startup & total costs equal to total cost of input
4188 * plan; this only affects EXPLAIN display not decisions.
4189 */
4190 copy_plan_costsize(&hash_plan->plan, inner_plan);
4191 hash_plan->plan.startup_cost = hash_plan->plan.total_cost;
4192
4193 join_plan = make_hashjoin(tlist,
4194 joinclauses,
4195 otherclauses,
4196 hashclauses,
4197 outer_plan,
4198 (Plan *) hash_plan,
4199 best_path->jpath.jointype,
4200 best_path->jpath.inner_unique);
4201
4202 copy_generic_path_info(&join_plan->join.plan, &best_path->jpath.path);
4203
4204 return join_plan;
4205 }
4206
4207
4208 /*****************************************************************************
4209 *
4210 * SUPPORTING ROUTINES
4211 *
4212 *****************************************************************************/
4213
4214 /*
4215 * replace_nestloop_params
4216 * Replace outer-relation Vars and PlaceHolderVars in the given expression
4217 * with nestloop Params
4218 *
4219 * All Vars and PlaceHolderVars belonging to the relation(s) identified by
4220 * root->curOuterRels are replaced by Params, and entries are added to
4221 * root->curOuterParams if not already present.
4222 */
4223 static Node *
replace_nestloop_params(PlannerInfo * root,Node * expr)4224 replace_nestloop_params(PlannerInfo *root, Node *expr)
4225 {
4226 /* No setup needed for tree walk, so away we go */
4227 return replace_nestloop_params_mutator(expr, root);
4228 }
4229
4230 static Node *
replace_nestloop_params_mutator(Node * node,PlannerInfo * root)4231 replace_nestloop_params_mutator(Node *node, PlannerInfo *root)
4232 {
4233 if (node == NULL)
4234 return NULL;
4235 if (IsA(node, Var))
4236 {
4237 Var *var = (Var *) node;
4238
4239 /* Upper-level Vars should be long gone at this point */
4240 Assert(var->varlevelsup == 0);
4241 /* If not to be replaced, we can just return the Var unmodified */
4242 if (!bms_is_member(var->varno, root->curOuterRels))
4243 return node;
4244 /* Replace the Var with a nestloop Param */
4245 return (Node *) replace_nestloop_param_var(root, var);
4246 }
4247 if (IsA(node, PlaceHolderVar))
4248 {
4249 PlaceHolderVar *phv = (PlaceHolderVar *) node;
4250
4251 /* Upper-level PlaceHolderVars should be long gone at this point */
4252 Assert(phv->phlevelsup == 0);
4253
4254 /*
4255 * Check whether we need to replace the PHV. We use bms_overlap as a
4256 * cheap/quick test to see if the PHV might be evaluated in the outer
4257 * rels, and then grab its PlaceHolderInfo to tell for sure.
4258 */
4259 if (!bms_overlap(phv->phrels, root->curOuterRels) ||
4260 !bms_is_subset(find_placeholder_info(root, phv, false)->ph_eval_at,
4261 root->curOuterRels))
4262 {
4263 /*
4264 * We can't replace the whole PHV, but we might still need to
4265 * replace Vars or PHVs within its expression, in case it ends up
4266 * actually getting evaluated here. (It might get evaluated in
4267 * this plan node, or some child node; in the latter case we don't
4268 * really need to process the expression here, but we haven't got
4269 * enough info to tell if that's the case.) Flat-copy the PHV
4270 * node and then recurse on its expression.
4271 *
4272 * Note that after doing this, we might have different
4273 * representations of the contents of the same PHV in different
4274 * parts of the plan tree. This is OK because equal() will just
4275 * match on phid/phlevelsup, so setrefs.c will still recognize an
4276 * upper-level reference to a lower-level copy of the same PHV.
4277 */
4278 PlaceHolderVar *newphv = makeNode(PlaceHolderVar);
4279
4280 memcpy(newphv, phv, sizeof(PlaceHolderVar));
4281 newphv->phexpr = (Expr *)
4282 replace_nestloop_params_mutator((Node *) phv->phexpr,
4283 root);
4284 return (Node *) newphv;
4285 }
4286 /* Replace the PlaceHolderVar with a nestloop Param */
4287 return (Node *) replace_nestloop_param_placeholdervar(root, phv);
4288 }
4289 return expression_tree_mutator(node,
4290 replace_nestloop_params_mutator,
4291 (void *) root);
4292 }
4293
4294 /*
4295 * fix_indexqual_references
4296 * Adjust indexqual clauses to the form the executor's indexqual
4297 * machinery needs.
4298 *
4299 * We have four tasks here:
4300 * * Remove RestrictInfo nodes from the input clauses.
4301 * * Replace any outer-relation Var or PHV nodes with nestloop Params.
4302 * (XXX eventually, that responsibility should go elsewhere?)
4303 * * Index keys must be represented by Var nodes with varattno set to the
4304 * index's attribute number, not the attribute number in the original rel.
4305 * * If the index key is on the right, commute the clause to put it on the
4306 * left.
4307 *
4308 * The result is a modified copy of the path's indexquals list --- the
4309 * original is not changed. Note also that the copy shares no substructure
4310 * with the original; this is needed in case there is a subplan in it (we need
4311 * two separate copies of the subplan tree, or things will go awry).
4312 */
4313 static List *
fix_indexqual_references(PlannerInfo * root,IndexPath * index_path)4314 fix_indexqual_references(PlannerInfo *root, IndexPath *index_path)
4315 {
4316 IndexOptInfo *index = index_path->indexinfo;
4317 List *fixed_indexquals;
4318 ListCell *lcc,
4319 *lci;
4320
4321 fixed_indexquals = NIL;
4322
4323 forboth(lcc, index_path->indexquals, lci, index_path->indexqualcols)
4324 {
4325 RestrictInfo *rinfo = lfirst_node(RestrictInfo, lcc);
4326 int indexcol = lfirst_int(lci);
4327 Node *clause;
4328
4329 /*
4330 * Replace any outer-relation variables with nestloop params.
4331 *
4332 * This also makes a copy of the clause, so it's safe to modify it
4333 * in-place below.
4334 */
4335 clause = replace_nestloop_params(root, (Node *) rinfo->clause);
4336
4337 if (IsA(clause, OpExpr))
4338 {
4339 OpExpr *op = (OpExpr *) clause;
4340
4341 if (list_length(op->args) != 2)
4342 elog(ERROR, "indexqual clause is not binary opclause");
4343
4344 /*
4345 * Check to see if the indexkey is on the right; if so, commute
4346 * the clause. The indexkey should be the side that refers to
4347 * (only) the base relation.
4348 */
4349 if (!bms_equal(rinfo->left_relids, index->rel->relids))
4350 CommuteOpExpr(op);
4351
4352 /*
4353 * Now replace the indexkey expression with an index Var.
4354 */
4355 linitial(op->args) = fix_indexqual_operand(linitial(op->args),
4356 index,
4357 indexcol);
4358 }
4359 else if (IsA(clause, RowCompareExpr))
4360 {
4361 RowCompareExpr *rc = (RowCompareExpr *) clause;
4362 Expr *newrc;
4363 List *indexcolnos;
4364 bool var_on_left;
4365 ListCell *lca,
4366 *lcai;
4367
4368 /*
4369 * Re-discover which index columns are used in the rowcompare.
4370 */
4371 newrc = adjust_rowcompare_for_index(rc,
4372 index,
4373 indexcol,
4374 &indexcolnos,
4375 &var_on_left);
4376
4377 /*
4378 * Trouble if adjust_rowcompare_for_index thought the
4379 * RowCompareExpr didn't match the index as-is; the clause should
4380 * have gone through that routine already.
4381 */
4382 if (newrc != (Expr *) rc)
4383 elog(ERROR, "inconsistent results from adjust_rowcompare_for_index");
4384
4385 /*
4386 * Check to see if the indexkey is on the right; if so, commute
4387 * the clause.
4388 */
4389 if (!var_on_left)
4390 CommuteRowCompareExpr(rc);
4391
4392 /*
4393 * Now replace the indexkey expressions with index Vars.
4394 */
4395 Assert(list_length(rc->largs) == list_length(indexcolnos));
4396 forboth(lca, rc->largs, lcai, indexcolnos)
4397 {
4398 lfirst(lca) = fix_indexqual_operand(lfirst(lca),
4399 index,
4400 lfirst_int(lcai));
4401 }
4402 }
4403 else if (IsA(clause, ScalarArrayOpExpr))
4404 {
4405 ScalarArrayOpExpr *saop = (ScalarArrayOpExpr *) clause;
4406
4407 /* Never need to commute... */
4408
4409 /* Replace the indexkey expression with an index Var. */
4410 linitial(saop->args) = fix_indexqual_operand(linitial(saop->args),
4411 index,
4412 indexcol);
4413 }
4414 else if (IsA(clause, NullTest))
4415 {
4416 NullTest *nt = (NullTest *) clause;
4417
4418 /* Replace the indexkey expression with an index Var. */
4419 nt->arg = (Expr *) fix_indexqual_operand((Node *) nt->arg,
4420 index,
4421 indexcol);
4422 }
4423 else
4424 elog(ERROR, "unsupported indexqual type: %d",
4425 (int) nodeTag(clause));
4426
4427 fixed_indexquals = lappend(fixed_indexquals, clause);
4428 }
4429
4430 return fixed_indexquals;
4431 }
4432
4433 /*
4434 * fix_indexorderby_references
4435 * Adjust indexorderby clauses to the form the executor's index
4436 * machinery needs.
4437 *
4438 * This is a simplified version of fix_indexqual_references. The input does
4439 * not have RestrictInfo nodes, and we assume that indxpath.c already
4440 * commuted the clauses to put the index keys on the left. Also, we don't
4441 * bother to support any cases except simple OpExprs, since nothing else
4442 * is allowed for ordering operators.
4443 */
4444 static List *
fix_indexorderby_references(PlannerInfo * root,IndexPath * index_path)4445 fix_indexorderby_references(PlannerInfo *root, IndexPath *index_path)
4446 {
4447 IndexOptInfo *index = index_path->indexinfo;
4448 List *fixed_indexorderbys;
4449 ListCell *lcc,
4450 *lci;
4451
4452 fixed_indexorderbys = NIL;
4453
4454 forboth(lcc, index_path->indexorderbys, lci, index_path->indexorderbycols)
4455 {
4456 Node *clause = (Node *) lfirst(lcc);
4457 int indexcol = lfirst_int(lci);
4458
4459 /*
4460 * Replace any outer-relation variables with nestloop params.
4461 *
4462 * This also makes a copy of the clause, so it's safe to modify it
4463 * in-place below.
4464 */
4465 clause = replace_nestloop_params(root, clause);
4466
4467 if (IsA(clause, OpExpr))
4468 {
4469 OpExpr *op = (OpExpr *) clause;
4470
4471 if (list_length(op->args) != 2)
4472 elog(ERROR, "indexorderby clause is not binary opclause");
4473
4474 /*
4475 * Now replace the indexkey expression with an index Var.
4476 */
4477 linitial(op->args) = fix_indexqual_operand(linitial(op->args),
4478 index,
4479 indexcol);
4480 }
4481 else
4482 elog(ERROR, "unsupported indexorderby type: %d",
4483 (int) nodeTag(clause));
4484
4485 fixed_indexorderbys = lappend(fixed_indexorderbys, clause);
4486 }
4487
4488 return fixed_indexorderbys;
4489 }
4490
4491 /*
4492 * fix_indexqual_operand
4493 * Convert an indexqual expression to a Var referencing the index column.
4494 *
4495 * We represent index keys by Var nodes having varno == INDEX_VAR and varattno
4496 * equal to the index's attribute number (index column position).
4497 *
4498 * Most of the code here is just for sanity cross-checking that the given
4499 * expression actually matches the index column it's claimed to.
4500 */
4501 static Node *
fix_indexqual_operand(Node * node,IndexOptInfo * index,int indexcol)4502 fix_indexqual_operand(Node *node, IndexOptInfo *index, int indexcol)
4503 {
4504 Var *result;
4505 int pos;
4506 ListCell *indexpr_item;
4507
4508 /*
4509 * Remove any binary-compatible relabeling of the indexkey
4510 */
4511 if (IsA(node, RelabelType))
4512 node = (Node *) ((RelabelType *) node)->arg;
4513
4514 Assert(indexcol >= 0 && indexcol < index->ncolumns);
4515
4516 if (index->indexkeys[indexcol] != 0)
4517 {
4518 /* It's a simple index column */
4519 if (IsA(node, Var) &&
4520 ((Var *) node)->varno == index->rel->relid &&
4521 ((Var *) node)->varattno == index->indexkeys[indexcol])
4522 {
4523 result = (Var *) copyObject(node);
4524 result->varno = INDEX_VAR;
4525 result->varattno = indexcol + 1;
4526 return (Node *) result;
4527 }
4528 else
4529 elog(ERROR, "index key does not match expected index column");
4530 }
4531
4532 /* It's an index expression, so find and cross-check the expression */
4533 indexpr_item = list_head(index->indexprs);
4534 for (pos = 0; pos < index->ncolumns; pos++)
4535 {
4536 if (index->indexkeys[pos] == 0)
4537 {
4538 if (indexpr_item == NULL)
4539 elog(ERROR, "too few entries in indexprs list");
4540 if (pos == indexcol)
4541 {
4542 Node *indexkey;
4543
4544 indexkey = (Node *) lfirst(indexpr_item);
4545 if (indexkey && IsA(indexkey, RelabelType))
4546 indexkey = (Node *) ((RelabelType *) indexkey)->arg;
4547 if (equal(node, indexkey))
4548 {
4549 result = makeVar(INDEX_VAR, indexcol + 1,
4550 exprType(lfirst(indexpr_item)), -1,
4551 exprCollation(lfirst(indexpr_item)),
4552 0);
4553 return (Node *) result;
4554 }
4555 else
4556 elog(ERROR, "index key does not match expected index column");
4557 }
4558 indexpr_item = lnext(indexpr_item);
4559 }
4560 }
4561
4562 /* Oops... */
4563 elog(ERROR, "index key does not match expected index column");
4564 return NULL; /* keep compiler quiet */
4565 }
4566
4567 /*
4568 * get_switched_clauses
4569 * Given a list of merge or hash joinclauses (as RestrictInfo nodes),
4570 * extract the bare clauses, and rearrange the elements within the
4571 * clauses, if needed, so the outer join variable is on the left and
4572 * the inner is on the right. The original clause data structure is not
4573 * touched; a modified list is returned. We do, however, set the transient
4574 * outer_is_left field in each RestrictInfo to show which side was which.
4575 */
4576 static List *
get_switched_clauses(List * clauses,Relids outerrelids)4577 get_switched_clauses(List *clauses, Relids outerrelids)
4578 {
4579 List *t_list = NIL;
4580 ListCell *l;
4581
4582 foreach(l, clauses)
4583 {
4584 RestrictInfo *restrictinfo = (RestrictInfo *) lfirst(l);
4585 OpExpr *clause = (OpExpr *) restrictinfo->clause;
4586
4587 Assert(is_opclause(clause));
4588 if (bms_is_subset(restrictinfo->right_relids, outerrelids))
4589 {
4590 /*
4591 * Duplicate just enough of the structure to allow commuting the
4592 * clause without changing the original list. Could use
4593 * copyObject, but a complete deep copy is overkill.
4594 */
4595 OpExpr *temp = makeNode(OpExpr);
4596
4597 temp->opno = clause->opno;
4598 temp->opfuncid = InvalidOid;
4599 temp->opresulttype = clause->opresulttype;
4600 temp->opretset = clause->opretset;
4601 temp->opcollid = clause->opcollid;
4602 temp->inputcollid = clause->inputcollid;
4603 temp->args = list_copy(clause->args);
4604 temp->location = clause->location;
4605 /* Commute it --- note this modifies the temp node in-place. */
4606 CommuteOpExpr(temp);
4607 t_list = lappend(t_list, temp);
4608 restrictinfo->outer_is_left = false;
4609 }
4610 else
4611 {
4612 Assert(bms_is_subset(restrictinfo->left_relids, outerrelids));
4613 t_list = lappend(t_list, clause);
4614 restrictinfo->outer_is_left = true;
4615 }
4616 }
4617 return t_list;
4618 }
4619
4620 /*
4621 * order_qual_clauses
4622 * Given a list of qual clauses that will all be evaluated at the same
4623 * plan node, sort the list into the order we want to check the quals
4624 * in at runtime.
4625 *
4626 * When security barrier quals are used in the query, we may have quals with
4627 * different security levels in the list. Quals of lower security_level
4628 * must go before quals of higher security_level, except that we can grant
4629 * exceptions to move up quals that are leakproof. When security level
4630 * doesn't force the decision, we prefer to order clauses by estimated
4631 * execution cost, cheapest first.
4632 *
4633 * Ideally the order should be driven by a combination of execution cost and
4634 * selectivity, but it's not immediately clear how to account for both,
4635 * and given the uncertainty of the estimates the reliability of the decisions
4636 * would be doubtful anyway. So we just order by security level then
4637 * estimated per-tuple cost, being careful not to change the order when
4638 * (as is often the case) the estimates are identical.
4639 *
4640 * Although this will work on either bare clauses or RestrictInfos, it's
4641 * much faster to apply it to RestrictInfos, since it can re-use cost
4642 * information that is cached in RestrictInfos. XXX in the bare-clause
4643 * case, we are also not able to apply security considerations. That is
4644 * all right for the moment, because the bare-clause case doesn't occur
4645 * anywhere that barrier quals could be present, but it would be better to
4646 * get rid of it.
4647 *
4648 * Note: some callers pass lists that contain entries that will later be
4649 * removed; this is the easiest way to let this routine see RestrictInfos
4650 * instead of bare clauses. This is another reason why trying to consider
4651 * selectivity in the ordering would likely do the wrong thing.
4652 */
4653 static List *
order_qual_clauses(PlannerInfo * root,List * clauses)4654 order_qual_clauses(PlannerInfo *root, List *clauses)
4655 {
4656 typedef struct
4657 {
4658 Node *clause;
4659 Cost cost;
4660 Index security_level;
4661 } QualItem;
4662 int nitems = list_length(clauses);
4663 QualItem *items;
4664 ListCell *lc;
4665 int i;
4666 List *result;
4667
4668 /* No need to work hard for 0 or 1 clause */
4669 if (nitems <= 1)
4670 return clauses;
4671
4672 /*
4673 * Collect the items and costs into an array. This is to avoid repeated
4674 * cost_qual_eval work if the inputs aren't RestrictInfos.
4675 */
4676 items = (QualItem *) palloc(nitems * sizeof(QualItem));
4677 i = 0;
4678 foreach(lc, clauses)
4679 {
4680 Node *clause = (Node *) lfirst(lc);
4681 QualCost qcost;
4682
4683 cost_qual_eval_node(&qcost, clause, root);
4684 items[i].clause = clause;
4685 items[i].cost = qcost.per_tuple;
4686 if (IsA(clause, RestrictInfo))
4687 {
4688 RestrictInfo *rinfo = (RestrictInfo *) clause;
4689
4690 /*
4691 * If a clause is leakproof, it doesn't have to be constrained by
4692 * its nominal security level. If it's also reasonably cheap
4693 * (here defined as 10X cpu_operator_cost), pretend it has
4694 * security_level 0, which will allow it to go in front of
4695 * more-expensive quals of lower security levels. Of course, that
4696 * will also force it to go in front of cheaper quals of its own
4697 * security level, which is not so great, but we can alleviate
4698 * that risk by applying the cost limit cutoff.
4699 */
4700 if (rinfo->leakproof && items[i].cost < 10 * cpu_operator_cost)
4701 items[i].security_level = 0;
4702 else
4703 items[i].security_level = rinfo->security_level;
4704 }
4705 else
4706 items[i].security_level = 0;
4707 i++;
4708 }
4709
4710 /*
4711 * Sort. We don't use qsort() because it's not guaranteed stable for
4712 * equal keys. The expected number of entries is small enough that a
4713 * simple insertion sort should be good enough.
4714 */
4715 for (i = 1; i < nitems; i++)
4716 {
4717 QualItem newitem = items[i];
4718 int j;
4719
4720 /* insert newitem into the already-sorted subarray */
4721 for (j = i; j > 0; j--)
4722 {
4723 QualItem *olditem = &items[j - 1];
4724
4725 if (newitem.security_level > olditem->security_level ||
4726 (newitem.security_level == olditem->security_level &&
4727 newitem.cost >= olditem->cost))
4728 break;
4729 items[j] = *olditem;
4730 }
4731 items[j] = newitem;
4732 }
4733
4734 /* Convert back to a list */
4735 result = NIL;
4736 for (i = 0; i < nitems; i++)
4737 result = lappend(result, items[i].clause);
4738
4739 return result;
4740 }
4741
4742 /*
4743 * Copy cost and size info from a Path node to the Plan node created from it.
4744 * The executor usually won't use this info, but it's needed by EXPLAIN.
4745 * Also copy the parallel-related flags, which the executor *will* use.
4746 */
4747 static void
copy_generic_path_info(Plan * dest,Path * src)4748 copy_generic_path_info(Plan *dest, Path *src)
4749 {
4750 dest->startup_cost = src->startup_cost;
4751 dest->total_cost = src->total_cost;
4752 dest->plan_rows = src->rows;
4753 dest->plan_width = src->pathtarget->width;
4754 dest->parallel_aware = src->parallel_aware;
4755 dest->parallel_safe = src->parallel_safe;
4756 }
4757
4758 /*
4759 * Copy cost and size info from a lower plan node to an inserted node.
4760 * (Most callers alter the info after copying it.)
4761 */
4762 static void
copy_plan_costsize(Plan * dest,Plan * src)4763 copy_plan_costsize(Plan *dest, Plan *src)
4764 {
4765 dest->startup_cost = src->startup_cost;
4766 dest->total_cost = src->total_cost;
4767 dest->plan_rows = src->plan_rows;
4768 dest->plan_width = src->plan_width;
4769 /* Assume the inserted node is not parallel-aware. */
4770 dest->parallel_aware = false;
4771 /* Assume the inserted node is parallel-safe, if child plan is. */
4772 dest->parallel_safe = src->parallel_safe;
4773 }
4774
4775 /*
4776 * Some places in this file build Sort nodes that don't have a directly
4777 * corresponding Path node. The cost of the sort is, or should have been,
4778 * included in the cost of the Path node we're working from, but since it's
4779 * not split out, we have to re-figure it using cost_sort(). This is just
4780 * to label the Sort node nicely for EXPLAIN.
4781 *
4782 * limit_tuples is as for cost_sort (in particular, pass -1 if no limit)
4783 */
4784 static void
label_sort_with_costsize(PlannerInfo * root,Sort * plan,double limit_tuples)4785 label_sort_with_costsize(PlannerInfo *root, Sort *plan, double limit_tuples)
4786 {
4787 Plan *lefttree = plan->plan.lefttree;
4788 Path sort_path; /* dummy for result of cost_sort */
4789
4790 cost_sort(&sort_path, root, NIL,
4791 lefttree->total_cost,
4792 lefttree->plan_rows,
4793 lefttree->plan_width,
4794 0.0,
4795 work_mem,
4796 limit_tuples);
4797 plan->plan.startup_cost = sort_path.startup_cost;
4798 plan->plan.total_cost = sort_path.total_cost;
4799 plan->plan.plan_rows = lefttree->plan_rows;
4800 plan->plan.plan_width = lefttree->plan_width;
4801 plan->plan.parallel_aware = false;
4802 plan->plan.parallel_safe = lefttree->parallel_safe;
4803 }
4804
4805 /*
4806 * bitmap_subplan_mark_shared
4807 * Set isshared flag in bitmap subplan so that it will be created in
4808 * shared memory.
4809 */
4810 static void
bitmap_subplan_mark_shared(Plan * plan)4811 bitmap_subplan_mark_shared(Plan *plan)
4812 {
4813 if (IsA(plan, BitmapAnd))
4814 bitmap_subplan_mark_shared(
4815 linitial(((BitmapAnd *) plan)->bitmapplans));
4816 else if (IsA(plan, BitmapOr))
4817 {
4818 ((BitmapOr *) plan)->isshared = true;
4819 bitmap_subplan_mark_shared(
4820 linitial(((BitmapOr *) plan)->bitmapplans));
4821 }
4822 else if (IsA(plan, BitmapIndexScan))
4823 ((BitmapIndexScan *) plan)->isshared = true;
4824 else
4825 elog(ERROR, "unrecognized node type: %d", nodeTag(plan));
4826 }
4827
4828 /*****************************************************************************
4829 *
4830 * PLAN NODE BUILDING ROUTINES
4831 *
4832 * In general, these functions are not passed the original Path and therefore
4833 * leave it to the caller to fill in the cost/width fields from the Path,
4834 * typically by calling copy_generic_path_info(). This convention is
4835 * somewhat historical, but it does support a few places above where we build
4836 * a plan node without having an exactly corresponding Path node. Under no
4837 * circumstances should one of these functions do its own cost calculations,
4838 * as that would be redundant with calculations done while building Paths.
4839 *
4840 *****************************************************************************/
4841
4842 static SeqScan *
make_seqscan(List * qptlist,List * qpqual,Index scanrelid)4843 make_seqscan(List *qptlist,
4844 List *qpqual,
4845 Index scanrelid)
4846 {
4847 SeqScan *node = makeNode(SeqScan);
4848 Plan *plan = &node->plan;
4849
4850 plan->targetlist = qptlist;
4851 plan->qual = qpqual;
4852 plan->lefttree = NULL;
4853 plan->righttree = NULL;
4854 node->scanrelid = scanrelid;
4855
4856 return node;
4857 }
4858
4859 static SampleScan *
make_samplescan(List * qptlist,List * qpqual,Index scanrelid,TableSampleClause * tsc)4860 make_samplescan(List *qptlist,
4861 List *qpqual,
4862 Index scanrelid,
4863 TableSampleClause *tsc)
4864 {
4865 SampleScan *node = makeNode(SampleScan);
4866 Plan *plan = &node->scan.plan;
4867
4868 plan->targetlist = qptlist;
4869 plan->qual = qpqual;
4870 plan->lefttree = NULL;
4871 plan->righttree = NULL;
4872 node->scan.scanrelid = scanrelid;
4873 node->tablesample = tsc;
4874
4875 return node;
4876 }
4877
4878 static IndexScan *
make_indexscan(List * qptlist,List * qpqual,Index scanrelid,Oid indexid,List * indexqual,List * indexqualorig,List * indexorderby,List * indexorderbyorig,List * indexorderbyops,ScanDirection indexscandir)4879 make_indexscan(List *qptlist,
4880 List *qpqual,
4881 Index scanrelid,
4882 Oid indexid,
4883 List *indexqual,
4884 List *indexqualorig,
4885 List *indexorderby,
4886 List *indexorderbyorig,
4887 List *indexorderbyops,
4888 ScanDirection indexscandir)
4889 {
4890 IndexScan *node = makeNode(IndexScan);
4891 Plan *plan = &node->scan.plan;
4892
4893 plan->targetlist = qptlist;
4894 plan->qual = qpqual;
4895 plan->lefttree = NULL;
4896 plan->righttree = NULL;
4897 node->scan.scanrelid = scanrelid;
4898 node->indexid = indexid;
4899 node->indexqual = indexqual;
4900 node->indexqualorig = indexqualorig;
4901 node->indexorderby = indexorderby;
4902 node->indexorderbyorig = indexorderbyorig;
4903 node->indexorderbyops = indexorderbyops;
4904 node->indexorderdir = indexscandir;
4905
4906 return node;
4907 }
4908
4909 static IndexOnlyScan *
make_indexonlyscan(List * qptlist,List * qpqual,Index scanrelid,Oid indexid,List * indexqual,List * indexorderby,List * indextlist,ScanDirection indexscandir)4910 make_indexonlyscan(List *qptlist,
4911 List *qpqual,
4912 Index scanrelid,
4913 Oid indexid,
4914 List *indexqual,
4915 List *indexorderby,
4916 List *indextlist,
4917 ScanDirection indexscandir)
4918 {
4919 IndexOnlyScan *node = makeNode(IndexOnlyScan);
4920 Plan *plan = &node->scan.plan;
4921
4922 plan->targetlist = qptlist;
4923 plan->qual = qpqual;
4924 plan->lefttree = NULL;
4925 plan->righttree = NULL;
4926 node->scan.scanrelid = scanrelid;
4927 node->indexid = indexid;
4928 node->indexqual = indexqual;
4929 node->indexorderby = indexorderby;
4930 node->indextlist = indextlist;
4931 node->indexorderdir = indexscandir;
4932
4933 return node;
4934 }
4935
4936 static BitmapIndexScan *
make_bitmap_indexscan(Index scanrelid,Oid indexid,List * indexqual,List * indexqualorig)4937 make_bitmap_indexscan(Index scanrelid,
4938 Oid indexid,
4939 List *indexqual,
4940 List *indexqualorig)
4941 {
4942 BitmapIndexScan *node = makeNode(BitmapIndexScan);
4943 Plan *plan = &node->scan.plan;
4944
4945 plan->targetlist = NIL; /* not used */
4946 plan->qual = NIL; /* not used */
4947 plan->lefttree = NULL;
4948 plan->righttree = NULL;
4949 node->scan.scanrelid = scanrelid;
4950 node->indexid = indexid;
4951 node->indexqual = indexqual;
4952 node->indexqualorig = indexqualorig;
4953
4954 return node;
4955 }
4956
4957 static BitmapHeapScan *
make_bitmap_heapscan(List * qptlist,List * qpqual,Plan * lefttree,List * bitmapqualorig,Index scanrelid)4958 make_bitmap_heapscan(List *qptlist,
4959 List *qpqual,
4960 Plan *lefttree,
4961 List *bitmapqualorig,
4962 Index scanrelid)
4963 {
4964 BitmapHeapScan *node = makeNode(BitmapHeapScan);
4965 Plan *plan = &node->scan.plan;
4966
4967 plan->targetlist = qptlist;
4968 plan->qual = qpqual;
4969 plan->lefttree = lefttree;
4970 plan->righttree = NULL;
4971 node->scan.scanrelid = scanrelid;
4972 node->bitmapqualorig = bitmapqualorig;
4973
4974 return node;
4975 }
4976
4977 static TidScan *
make_tidscan(List * qptlist,List * qpqual,Index scanrelid,List * tidquals)4978 make_tidscan(List *qptlist,
4979 List *qpqual,
4980 Index scanrelid,
4981 List *tidquals)
4982 {
4983 TidScan *node = makeNode(TidScan);
4984 Plan *plan = &node->scan.plan;
4985
4986 plan->targetlist = qptlist;
4987 plan->qual = qpqual;
4988 plan->lefttree = NULL;
4989 plan->righttree = NULL;
4990 node->scan.scanrelid = scanrelid;
4991 node->tidquals = tidquals;
4992
4993 return node;
4994 }
4995
4996 static SubqueryScan *
make_subqueryscan(List * qptlist,List * qpqual,Index scanrelid,Plan * subplan)4997 make_subqueryscan(List *qptlist,
4998 List *qpqual,
4999 Index scanrelid,
5000 Plan *subplan)
5001 {
5002 SubqueryScan *node = makeNode(SubqueryScan);
5003 Plan *plan = &node->scan.plan;
5004
5005 plan->targetlist = qptlist;
5006 plan->qual = qpqual;
5007 plan->lefttree = NULL;
5008 plan->righttree = NULL;
5009 node->scan.scanrelid = scanrelid;
5010 node->subplan = subplan;
5011
5012 return node;
5013 }
5014
5015 static FunctionScan *
make_functionscan(List * qptlist,List * qpqual,Index scanrelid,List * functions,bool funcordinality)5016 make_functionscan(List *qptlist,
5017 List *qpqual,
5018 Index scanrelid,
5019 List *functions,
5020 bool funcordinality)
5021 {
5022 FunctionScan *node = makeNode(FunctionScan);
5023 Plan *plan = &node->scan.plan;
5024
5025 plan->targetlist = qptlist;
5026 plan->qual = qpqual;
5027 plan->lefttree = NULL;
5028 plan->righttree = NULL;
5029 node->scan.scanrelid = scanrelid;
5030 node->functions = functions;
5031 node->funcordinality = funcordinality;
5032
5033 return node;
5034 }
5035
5036 static TableFuncScan *
make_tablefuncscan(List * qptlist,List * qpqual,Index scanrelid,TableFunc * tablefunc)5037 make_tablefuncscan(List *qptlist,
5038 List *qpqual,
5039 Index scanrelid,
5040 TableFunc *tablefunc)
5041 {
5042 TableFuncScan *node = makeNode(TableFuncScan);
5043 Plan *plan = &node->scan.plan;
5044
5045 plan->targetlist = qptlist;
5046 plan->qual = qpqual;
5047 plan->lefttree = NULL;
5048 plan->righttree = NULL;
5049 node->scan.scanrelid = scanrelid;
5050 node->tablefunc = tablefunc;
5051
5052 return node;
5053 }
5054
5055 static ValuesScan *
make_valuesscan(List * qptlist,List * qpqual,Index scanrelid,List * values_lists)5056 make_valuesscan(List *qptlist,
5057 List *qpqual,
5058 Index scanrelid,
5059 List *values_lists)
5060 {
5061 ValuesScan *node = makeNode(ValuesScan);
5062 Plan *plan = &node->scan.plan;
5063
5064 plan->targetlist = qptlist;
5065 plan->qual = qpqual;
5066 plan->lefttree = NULL;
5067 plan->righttree = NULL;
5068 node->scan.scanrelid = scanrelid;
5069 node->values_lists = values_lists;
5070
5071 return node;
5072 }
5073
5074 static CteScan *
make_ctescan(List * qptlist,List * qpqual,Index scanrelid,int ctePlanId,int cteParam)5075 make_ctescan(List *qptlist,
5076 List *qpqual,
5077 Index scanrelid,
5078 int ctePlanId,
5079 int cteParam)
5080 {
5081 CteScan *node = makeNode(CteScan);
5082 Plan *plan = &node->scan.plan;
5083
5084 plan->targetlist = qptlist;
5085 plan->qual = qpqual;
5086 plan->lefttree = NULL;
5087 plan->righttree = NULL;
5088 node->scan.scanrelid = scanrelid;
5089 node->ctePlanId = ctePlanId;
5090 node->cteParam = cteParam;
5091
5092 return node;
5093 }
5094
5095 static NamedTuplestoreScan *
make_namedtuplestorescan(List * qptlist,List * qpqual,Index scanrelid,char * enrname)5096 make_namedtuplestorescan(List *qptlist,
5097 List *qpqual,
5098 Index scanrelid,
5099 char *enrname)
5100 {
5101 NamedTuplestoreScan *node = makeNode(NamedTuplestoreScan);
5102 Plan *plan = &node->scan.plan;
5103
5104 /* cost should be inserted by caller */
5105 plan->targetlist = qptlist;
5106 plan->qual = qpqual;
5107 plan->lefttree = NULL;
5108 plan->righttree = NULL;
5109 node->scan.scanrelid = scanrelid;
5110 node->enrname = enrname;
5111
5112 return node;
5113 }
5114
5115 static WorkTableScan *
make_worktablescan(List * qptlist,List * qpqual,Index scanrelid,int wtParam)5116 make_worktablescan(List *qptlist,
5117 List *qpqual,
5118 Index scanrelid,
5119 int wtParam)
5120 {
5121 WorkTableScan *node = makeNode(WorkTableScan);
5122 Plan *plan = &node->scan.plan;
5123
5124 plan->targetlist = qptlist;
5125 plan->qual = qpqual;
5126 plan->lefttree = NULL;
5127 plan->righttree = NULL;
5128 node->scan.scanrelid = scanrelid;
5129 node->wtParam = wtParam;
5130
5131 return node;
5132 }
5133
5134 ForeignScan *
make_foreignscan(List * qptlist,List * qpqual,Index scanrelid,List * fdw_exprs,List * fdw_private,List * fdw_scan_tlist,List * fdw_recheck_quals,Plan * outer_plan)5135 make_foreignscan(List *qptlist,
5136 List *qpqual,
5137 Index scanrelid,
5138 List *fdw_exprs,
5139 List *fdw_private,
5140 List *fdw_scan_tlist,
5141 List *fdw_recheck_quals,
5142 Plan *outer_plan)
5143 {
5144 ForeignScan *node = makeNode(ForeignScan);
5145 Plan *plan = &node->scan.plan;
5146
5147 /* cost will be filled in by create_foreignscan_plan */
5148 plan->targetlist = qptlist;
5149 plan->qual = qpqual;
5150 plan->lefttree = outer_plan;
5151 plan->righttree = NULL;
5152 node->scan.scanrelid = scanrelid;
5153 node->operation = CMD_SELECT;
5154 /* fs_server will be filled in by create_foreignscan_plan */
5155 node->fs_server = InvalidOid;
5156 node->fdw_exprs = fdw_exprs;
5157 node->fdw_private = fdw_private;
5158 node->fdw_scan_tlist = fdw_scan_tlist;
5159 node->fdw_recheck_quals = fdw_recheck_quals;
5160 /* fs_relids will be filled in by create_foreignscan_plan */
5161 node->fs_relids = NULL;
5162 /* fsSystemCol will be filled in by create_foreignscan_plan */
5163 node->fsSystemCol = false;
5164
5165 return node;
5166 }
5167
5168 static Append *
make_append(List * appendplans,List * tlist,List * partitioned_rels)5169 make_append(List *appendplans, List *tlist, List *partitioned_rels)
5170 {
5171 Append *node = makeNode(Append);
5172 Plan *plan = &node->plan;
5173
5174 plan->targetlist = tlist;
5175 plan->qual = NIL;
5176 plan->lefttree = NULL;
5177 plan->righttree = NULL;
5178 node->partitioned_rels = partitioned_rels;
5179 node->appendplans = appendplans;
5180
5181 return node;
5182 }
5183
5184 static RecursiveUnion *
make_recursive_union(List * tlist,Plan * lefttree,Plan * righttree,int wtParam,List * distinctList,long numGroups)5185 make_recursive_union(List *tlist,
5186 Plan *lefttree,
5187 Plan *righttree,
5188 int wtParam,
5189 List *distinctList,
5190 long numGroups)
5191 {
5192 RecursiveUnion *node = makeNode(RecursiveUnion);
5193 Plan *plan = &node->plan;
5194 int numCols = list_length(distinctList);
5195
5196 plan->targetlist = tlist;
5197 plan->qual = NIL;
5198 plan->lefttree = lefttree;
5199 plan->righttree = righttree;
5200 node->wtParam = wtParam;
5201
5202 /*
5203 * convert SortGroupClause list into arrays of attr indexes and equality
5204 * operators, as wanted by executor
5205 */
5206 node->numCols = numCols;
5207 if (numCols > 0)
5208 {
5209 int keyno = 0;
5210 AttrNumber *dupColIdx;
5211 Oid *dupOperators;
5212 ListCell *slitem;
5213
5214 dupColIdx = (AttrNumber *) palloc(sizeof(AttrNumber) * numCols);
5215 dupOperators = (Oid *) palloc(sizeof(Oid) * numCols);
5216
5217 foreach(slitem, distinctList)
5218 {
5219 SortGroupClause *sortcl = (SortGroupClause *) lfirst(slitem);
5220 TargetEntry *tle = get_sortgroupclause_tle(sortcl,
5221 plan->targetlist);
5222
5223 dupColIdx[keyno] = tle->resno;
5224 dupOperators[keyno] = sortcl->eqop;
5225 Assert(OidIsValid(dupOperators[keyno]));
5226 keyno++;
5227 }
5228 node->dupColIdx = dupColIdx;
5229 node->dupOperators = dupOperators;
5230 }
5231 node->numGroups = numGroups;
5232
5233 return node;
5234 }
5235
5236 static BitmapAnd *
make_bitmap_and(List * bitmapplans)5237 make_bitmap_and(List *bitmapplans)
5238 {
5239 BitmapAnd *node = makeNode(BitmapAnd);
5240 Plan *plan = &node->plan;
5241
5242 plan->targetlist = NIL;
5243 plan->qual = NIL;
5244 plan->lefttree = NULL;
5245 plan->righttree = NULL;
5246 node->bitmapplans = bitmapplans;
5247
5248 return node;
5249 }
5250
5251 static BitmapOr *
make_bitmap_or(List * bitmapplans)5252 make_bitmap_or(List *bitmapplans)
5253 {
5254 BitmapOr *node = makeNode(BitmapOr);
5255 Plan *plan = &node->plan;
5256
5257 plan->targetlist = NIL;
5258 plan->qual = NIL;
5259 plan->lefttree = NULL;
5260 plan->righttree = NULL;
5261 node->bitmapplans = bitmapplans;
5262
5263 return node;
5264 }
5265
5266 static NestLoop *
make_nestloop(List * tlist,List * joinclauses,List * otherclauses,List * nestParams,Plan * lefttree,Plan * righttree,JoinType jointype,bool inner_unique)5267 make_nestloop(List *tlist,
5268 List *joinclauses,
5269 List *otherclauses,
5270 List *nestParams,
5271 Plan *lefttree,
5272 Plan *righttree,
5273 JoinType jointype,
5274 bool inner_unique)
5275 {
5276 NestLoop *node = makeNode(NestLoop);
5277 Plan *plan = &node->join.plan;
5278
5279 plan->targetlist = tlist;
5280 plan->qual = otherclauses;
5281 plan->lefttree = lefttree;
5282 plan->righttree = righttree;
5283 node->join.jointype = jointype;
5284 node->join.inner_unique = inner_unique;
5285 node->join.joinqual = joinclauses;
5286 node->nestParams = nestParams;
5287
5288 return node;
5289 }
5290
5291 static HashJoin *
make_hashjoin(List * tlist,List * joinclauses,List * otherclauses,List * hashclauses,Plan * lefttree,Plan * righttree,JoinType jointype,bool inner_unique)5292 make_hashjoin(List *tlist,
5293 List *joinclauses,
5294 List *otherclauses,
5295 List *hashclauses,
5296 Plan *lefttree,
5297 Plan *righttree,
5298 JoinType jointype,
5299 bool inner_unique)
5300 {
5301 HashJoin *node = makeNode(HashJoin);
5302 Plan *plan = &node->join.plan;
5303
5304 plan->targetlist = tlist;
5305 plan->qual = otherclauses;
5306 plan->lefttree = lefttree;
5307 plan->righttree = righttree;
5308 node->hashclauses = hashclauses;
5309 node->join.jointype = jointype;
5310 node->join.inner_unique = inner_unique;
5311 node->join.joinqual = joinclauses;
5312
5313 return node;
5314 }
5315
5316 static Hash *
make_hash(Plan * lefttree,Oid skewTable,AttrNumber skewColumn,bool skewInherit)5317 make_hash(Plan *lefttree,
5318 Oid skewTable,
5319 AttrNumber skewColumn,
5320 bool skewInherit)
5321 {
5322 Hash *node = makeNode(Hash);
5323 Plan *plan = &node->plan;
5324
5325 plan->targetlist = lefttree->targetlist;
5326 plan->qual = NIL;
5327 plan->lefttree = lefttree;
5328 plan->righttree = NULL;
5329
5330 node->skewTable = skewTable;
5331 node->skewColumn = skewColumn;
5332 node->skewInherit = skewInherit;
5333
5334 return node;
5335 }
5336
5337 static MergeJoin *
make_mergejoin(List * tlist,List * joinclauses,List * otherclauses,List * mergeclauses,Oid * mergefamilies,Oid * mergecollations,int * mergestrategies,bool * mergenullsfirst,Plan * lefttree,Plan * righttree,JoinType jointype,bool inner_unique,bool skip_mark_restore)5338 make_mergejoin(List *tlist,
5339 List *joinclauses,
5340 List *otherclauses,
5341 List *mergeclauses,
5342 Oid *mergefamilies,
5343 Oid *mergecollations,
5344 int *mergestrategies,
5345 bool *mergenullsfirst,
5346 Plan *lefttree,
5347 Plan *righttree,
5348 JoinType jointype,
5349 bool inner_unique,
5350 bool skip_mark_restore)
5351 {
5352 MergeJoin *node = makeNode(MergeJoin);
5353 Plan *plan = &node->join.plan;
5354
5355 plan->targetlist = tlist;
5356 plan->qual = otherclauses;
5357 plan->lefttree = lefttree;
5358 plan->righttree = righttree;
5359 node->skip_mark_restore = skip_mark_restore;
5360 node->mergeclauses = mergeclauses;
5361 node->mergeFamilies = mergefamilies;
5362 node->mergeCollations = mergecollations;
5363 node->mergeStrategies = mergestrategies;
5364 node->mergeNullsFirst = mergenullsfirst;
5365 node->join.jointype = jointype;
5366 node->join.inner_unique = inner_unique;
5367 node->join.joinqual = joinclauses;
5368
5369 return node;
5370 }
5371
5372 /*
5373 * make_sort --- basic routine to build a Sort plan node
5374 *
5375 * Caller must have built the sortColIdx, sortOperators, collations, and
5376 * nullsFirst arrays already.
5377 */
5378 static Sort *
make_sort(Plan * lefttree,int numCols,AttrNumber * sortColIdx,Oid * sortOperators,Oid * collations,bool * nullsFirst)5379 make_sort(Plan *lefttree, int numCols,
5380 AttrNumber *sortColIdx, Oid *sortOperators,
5381 Oid *collations, bool *nullsFirst)
5382 {
5383 Sort *node = makeNode(Sort);
5384 Plan *plan = &node->plan;
5385
5386 plan->targetlist = lefttree->targetlist;
5387 plan->qual = NIL;
5388 plan->lefttree = lefttree;
5389 plan->righttree = NULL;
5390 node->numCols = numCols;
5391 node->sortColIdx = sortColIdx;
5392 node->sortOperators = sortOperators;
5393 node->collations = collations;
5394 node->nullsFirst = nullsFirst;
5395
5396 return node;
5397 }
5398
5399 /*
5400 * prepare_sort_from_pathkeys
5401 * Prepare to sort according to given pathkeys
5402 *
5403 * This is used to set up for Sort, MergeAppend, and Gather Merge nodes. It
5404 * calculates the executor's representation of the sort key information, and
5405 * adjusts the plan targetlist if needed to add resjunk sort columns.
5406 *
5407 * Input parameters:
5408 * 'lefttree' is the plan node which yields input tuples
5409 * 'pathkeys' is the list of pathkeys by which the result is to be sorted
5410 * 'relids' identifies the child relation being sorted, if any
5411 * 'reqColIdx' is NULL or an array of required sort key column numbers
5412 * 'adjust_tlist_in_place' is TRUE if lefttree must be modified in-place
5413 *
5414 * We must convert the pathkey information into arrays of sort key column
5415 * numbers, sort operator OIDs, collation OIDs, and nulls-first flags,
5416 * which is the representation the executor wants. These are returned into
5417 * the output parameters *p_numsortkeys etc.
5418 *
5419 * When looking for matches to an EquivalenceClass's members, we will only
5420 * consider child EC members if they match 'relids'. This protects against
5421 * possible incorrect matches to child expressions that contain no Vars.
5422 *
5423 * If reqColIdx isn't NULL then it contains sort key column numbers that
5424 * we should match. This is used when making child plans for a MergeAppend;
5425 * it's an error if we can't match the columns.
5426 *
5427 * If the pathkeys include expressions that aren't simple Vars, we will
5428 * usually need to add resjunk items to the input plan's targetlist to
5429 * compute these expressions, since a Sort or MergeAppend node itself won't
5430 * do any such calculations. If the input plan type isn't one that can do
5431 * projections, this means adding a Result node just to do the projection.
5432 * However, the caller can pass adjust_tlist_in_place = TRUE to force the
5433 * lefttree tlist to be modified in-place regardless of whether the node type
5434 * can project --- we use this for fixing the tlist of MergeAppend itself.
5435 *
5436 * Returns the node which is to be the input to the Sort (either lefttree,
5437 * or a Result stacked atop lefttree).
5438 */
5439 static Plan *
prepare_sort_from_pathkeys(Plan * lefttree,List * pathkeys,Relids relids,const AttrNumber * reqColIdx,bool adjust_tlist_in_place,int * p_numsortkeys,AttrNumber ** p_sortColIdx,Oid ** p_sortOperators,Oid ** p_collations,bool ** p_nullsFirst)5440 prepare_sort_from_pathkeys(Plan *lefttree, List *pathkeys,
5441 Relids relids,
5442 const AttrNumber *reqColIdx,
5443 bool adjust_tlist_in_place,
5444 int *p_numsortkeys,
5445 AttrNumber **p_sortColIdx,
5446 Oid **p_sortOperators,
5447 Oid **p_collations,
5448 bool **p_nullsFirst)
5449 {
5450 List *tlist = lefttree->targetlist;
5451 ListCell *i;
5452 int numsortkeys;
5453 AttrNumber *sortColIdx;
5454 Oid *sortOperators;
5455 Oid *collations;
5456 bool *nullsFirst;
5457
5458 /*
5459 * We will need at most list_length(pathkeys) sort columns; possibly less
5460 */
5461 numsortkeys = list_length(pathkeys);
5462 sortColIdx = (AttrNumber *) palloc(numsortkeys * sizeof(AttrNumber));
5463 sortOperators = (Oid *) palloc(numsortkeys * sizeof(Oid));
5464 collations = (Oid *) palloc(numsortkeys * sizeof(Oid));
5465 nullsFirst = (bool *) palloc(numsortkeys * sizeof(bool));
5466
5467 numsortkeys = 0;
5468
5469 foreach(i, pathkeys)
5470 {
5471 PathKey *pathkey = (PathKey *) lfirst(i);
5472 EquivalenceClass *ec = pathkey->pk_eclass;
5473 EquivalenceMember *em;
5474 TargetEntry *tle = NULL;
5475 Oid pk_datatype = InvalidOid;
5476 Oid sortop;
5477 ListCell *j;
5478
5479 if (ec->ec_has_volatile)
5480 {
5481 /*
5482 * If the pathkey's EquivalenceClass is volatile, then it must
5483 * have come from an ORDER BY clause, and we have to match it to
5484 * that same targetlist entry.
5485 */
5486 if (ec->ec_sortref == 0) /* can't happen */
5487 elog(ERROR, "volatile EquivalenceClass has no sortref");
5488 tle = get_sortgroupref_tle(ec->ec_sortref, tlist);
5489 Assert(tle);
5490 Assert(list_length(ec->ec_members) == 1);
5491 pk_datatype = ((EquivalenceMember *) linitial(ec->ec_members))->em_datatype;
5492 }
5493 else if (reqColIdx != NULL)
5494 {
5495 /*
5496 * If we are given a sort column number to match, only consider
5497 * the single TLE at that position. It's possible that there is
5498 * no such TLE, in which case fall through and generate a resjunk
5499 * targetentry (we assume this must have happened in the parent
5500 * plan as well). If there is a TLE but it doesn't match the
5501 * pathkey's EC, we do the same, which is probably the wrong thing
5502 * but we'll leave it to caller to complain about the mismatch.
5503 */
5504 tle = get_tle_by_resno(tlist, reqColIdx[numsortkeys]);
5505 if (tle)
5506 {
5507 em = find_ec_member_for_tle(ec, tle, relids);
5508 if (em)
5509 {
5510 /* found expr at right place in tlist */
5511 pk_datatype = em->em_datatype;
5512 }
5513 else
5514 tle = NULL;
5515 }
5516 }
5517 else
5518 {
5519 /*
5520 * Otherwise, we can sort by any non-constant expression listed in
5521 * the pathkey's EquivalenceClass. For now, we take the first
5522 * tlist item found in the EC. If there's no match, we'll generate
5523 * a resjunk entry using the first EC member that is an expression
5524 * in the input's vars. (The non-const restriction only matters
5525 * if the EC is below_outer_join; but if it isn't, it won't
5526 * contain consts anyway, else we'd have discarded the pathkey as
5527 * redundant.)
5528 *
5529 * XXX if we have a choice, is there any way of figuring out which
5530 * might be cheapest to execute? (For example, int4lt is likely
5531 * much cheaper to execute than numericlt, but both might appear
5532 * in the same equivalence class...) Not clear that we ever will
5533 * have an interesting choice in practice, so it may not matter.
5534 */
5535 foreach(j, tlist)
5536 {
5537 tle = (TargetEntry *) lfirst(j);
5538 em = find_ec_member_for_tle(ec, tle, relids);
5539 if (em)
5540 {
5541 /* found expr already in tlist */
5542 pk_datatype = em->em_datatype;
5543 break;
5544 }
5545 tle = NULL;
5546 }
5547 }
5548
5549 if (!tle)
5550 {
5551 /*
5552 * No matching tlist item; look for a computable expression. Note
5553 * that we treat Aggrefs as if they were variables; this is
5554 * necessary when attempting to sort the output from an Agg node
5555 * for use in a WindowFunc (since grouping_planner will have
5556 * treated the Aggrefs as variables, too). Likewise, if we find a
5557 * WindowFunc in a sort expression, treat it as a variable.
5558 */
5559 Expr *sortexpr = NULL;
5560
5561 foreach(j, ec->ec_members)
5562 {
5563 EquivalenceMember *em = (EquivalenceMember *) lfirst(j);
5564 List *exprvars;
5565 ListCell *k;
5566
5567 /*
5568 * We shouldn't be trying to sort by an equivalence class that
5569 * contains a constant, so no need to consider such cases any
5570 * further.
5571 */
5572 if (em->em_is_const)
5573 continue;
5574
5575 /*
5576 * Ignore child members unless they match the rel being
5577 * sorted.
5578 */
5579 if (em->em_is_child &&
5580 !bms_equal(em->em_relids, relids))
5581 continue;
5582
5583 sortexpr = em->em_expr;
5584 exprvars = pull_var_clause((Node *) sortexpr,
5585 PVC_INCLUDE_AGGREGATES |
5586 PVC_INCLUDE_WINDOWFUNCS |
5587 PVC_INCLUDE_PLACEHOLDERS);
5588 foreach(k, exprvars)
5589 {
5590 if (!tlist_member_ignore_relabel(lfirst(k), tlist))
5591 break;
5592 }
5593 list_free(exprvars);
5594 if (!k)
5595 {
5596 pk_datatype = em->em_datatype;
5597 break; /* found usable expression */
5598 }
5599 }
5600 if (!j)
5601 elog(ERROR, "could not find pathkey item to sort");
5602
5603 /*
5604 * Do we need to insert a Result node?
5605 */
5606 if (!adjust_tlist_in_place &&
5607 !is_projection_capable_plan(lefttree))
5608 {
5609 /* copy needed so we don't modify input's tlist below */
5610 tlist = copyObject(tlist);
5611 lefttree = inject_projection_plan(lefttree, tlist,
5612 lefttree->parallel_safe);
5613 }
5614
5615 /* Don't bother testing is_projection_capable_plan again */
5616 adjust_tlist_in_place = true;
5617
5618 /*
5619 * Add resjunk entry to input's tlist
5620 */
5621 tle = makeTargetEntry(sortexpr,
5622 list_length(tlist) + 1,
5623 NULL,
5624 true);
5625 tlist = lappend(tlist, tle);
5626 lefttree->targetlist = tlist; /* just in case NIL before */
5627 }
5628
5629 /*
5630 * Look up the correct sort operator from the PathKey's slightly
5631 * abstracted representation.
5632 */
5633 sortop = get_opfamily_member(pathkey->pk_opfamily,
5634 pk_datatype,
5635 pk_datatype,
5636 pathkey->pk_strategy);
5637 if (!OidIsValid(sortop)) /* should not happen */
5638 elog(ERROR, "missing operator %d(%u,%u) in opfamily %u",
5639 pathkey->pk_strategy, pk_datatype, pk_datatype,
5640 pathkey->pk_opfamily);
5641
5642 /* Add the column to the sort arrays */
5643 sortColIdx[numsortkeys] = tle->resno;
5644 sortOperators[numsortkeys] = sortop;
5645 collations[numsortkeys] = ec->ec_collation;
5646 nullsFirst[numsortkeys] = pathkey->pk_nulls_first;
5647 numsortkeys++;
5648 }
5649
5650 /* Return results */
5651 *p_numsortkeys = numsortkeys;
5652 *p_sortColIdx = sortColIdx;
5653 *p_sortOperators = sortOperators;
5654 *p_collations = collations;
5655 *p_nullsFirst = nullsFirst;
5656
5657 return lefttree;
5658 }
5659
5660 /*
5661 * find_ec_member_for_tle
5662 * Locate an EquivalenceClass member matching the given TLE, if any
5663 *
5664 * Child EC members are ignored unless they match 'relids'.
5665 */
5666 static EquivalenceMember *
find_ec_member_for_tle(EquivalenceClass * ec,TargetEntry * tle,Relids relids)5667 find_ec_member_for_tle(EquivalenceClass *ec,
5668 TargetEntry *tle,
5669 Relids relids)
5670 {
5671 Expr *tlexpr;
5672 ListCell *lc;
5673
5674 /* We ignore binary-compatible relabeling on both ends */
5675 tlexpr = tle->expr;
5676 while (tlexpr && IsA(tlexpr, RelabelType))
5677 tlexpr = ((RelabelType *) tlexpr)->arg;
5678
5679 foreach(lc, ec->ec_members)
5680 {
5681 EquivalenceMember *em = (EquivalenceMember *) lfirst(lc);
5682 Expr *emexpr;
5683
5684 /*
5685 * We shouldn't be trying to sort by an equivalence class that
5686 * contains a constant, so no need to consider such cases any further.
5687 */
5688 if (em->em_is_const)
5689 continue;
5690
5691 /*
5692 * Ignore child members unless they match the rel being sorted.
5693 */
5694 if (em->em_is_child &&
5695 !bms_equal(em->em_relids, relids))
5696 continue;
5697
5698 /* Match if same expression (after stripping relabel) */
5699 emexpr = em->em_expr;
5700 while (emexpr && IsA(emexpr, RelabelType))
5701 emexpr = ((RelabelType *) emexpr)->arg;
5702
5703 if (equal(emexpr, tlexpr))
5704 return em;
5705 }
5706
5707 return NULL;
5708 }
5709
5710 /*
5711 * make_sort_from_pathkeys
5712 * Create sort plan to sort according to given pathkeys
5713 *
5714 * 'lefttree' is the node which yields input tuples
5715 * 'pathkeys' is the list of pathkeys by which the result is to be sorted
5716 */
5717 static Sort *
make_sort_from_pathkeys(Plan * lefttree,List * pathkeys)5718 make_sort_from_pathkeys(Plan *lefttree, List *pathkeys)
5719 {
5720 int numsortkeys;
5721 AttrNumber *sortColIdx;
5722 Oid *sortOperators;
5723 Oid *collations;
5724 bool *nullsFirst;
5725
5726 /* Compute sort column info, and adjust lefttree as needed */
5727 lefttree = prepare_sort_from_pathkeys(lefttree, pathkeys,
5728 NULL,
5729 NULL,
5730 false,
5731 &numsortkeys,
5732 &sortColIdx,
5733 &sortOperators,
5734 &collations,
5735 &nullsFirst);
5736
5737 /* Now build the Sort node */
5738 return make_sort(lefttree, numsortkeys,
5739 sortColIdx, sortOperators,
5740 collations, nullsFirst);
5741 }
5742
5743 /*
5744 * make_sort_from_sortclauses
5745 * Create sort plan to sort according to given sortclauses
5746 *
5747 * 'sortcls' is a list of SortGroupClauses
5748 * 'lefttree' is the node which yields input tuples
5749 */
5750 Sort *
make_sort_from_sortclauses(List * sortcls,Plan * lefttree)5751 make_sort_from_sortclauses(List *sortcls, Plan *lefttree)
5752 {
5753 List *sub_tlist = lefttree->targetlist;
5754 ListCell *l;
5755 int numsortkeys;
5756 AttrNumber *sortColIdx;
5757 Oid *sortOperators;
5758 Oid *collations;
5759 bool *nullsFirst;
5760
5761 /* Convert list-ish representation to arrays wanted by executor */
5762 numsortkeys = list_length(sortcls);
5763 sortColIdx = (AttrNumber *) palloc(numsortkeys * sizeof(AttrNumber));
5764 sortOperators = (Oid *) palloc(numsortkeys * sizeof(Oid));
5765 collations = (Oid *) palloc(numsortkeys * sizeof(Oid));
5766 nullsFirst = (bool *) palloc(numsortkeys * sizeof(bool));
5767
5768 numsortkeys = 0;
5769 foreach(l, sortcls)
5770 {
5771 SortGroupClause *sortcl = (SortGroupClause *) lfirst(l);
5772 TargetEntry *tle = get_sortgroupclause_tle(sortcl, sub_tlist);
5773
5774 sortColIdx[numsortkeys] = tle->resno;
5775 sortOperators[numsortkeys] = sortcl->sortop;
5776 collations[numsortkeys] = exprCollation((Node *) tle->expr);
5777 nullsFirst[numsortkeys] = sortcl->nulls_first;
5778 numsortkeys++;
5779 }
5780
5781 return make_sort(lefttree, numsortkeys,
5782 sortColIdx, sortOperators,
5783 collations, nullsFirst);
5784 }
5785
5786 /*
5787 * make_sort_from_groupcols
5788 * Create sort plan to sort based on grouping columns
5789 *
5790 * 'groupcls' is the list of SortGroupClauses
5791 * 'grpColIdx' gives the column numbers to use
5792 *
5793 * This might look like it could be merged with make_sort_from_sortclauses,
5794 * but presently we *must* use the grpColIdx[] array to locate sort columns,
5795 * because the child plan's tlist is not marked with ressortgroupref info
5796 * appropriate to the grouping node. So, only the sort ordering info
5797 * is used from the SortGroupClause entries.
5798 */
5799 static Sort *
make_sort_from_groupcols(List * groupcls,AttrNumber * grpColIdx,Plan * lefttree)5800 make_sort_from_groupcols(List *groupcls,
5801 AttrNumber *grpColIdx,
5802 Plan *lefttree)
5803 {
5804 List *sub_tlist = lefttree->targetlist;
5805 ListCell *l;
5806 int numsortkeys;
5807 AttrNumber *sortColIdx;
5808 Oid *sortOperators;
5809 Oid *collations;
5810 bool *nullsFirst;
5811
5812 /* Convert list-ish representation to arrays wanted by executor */
5813 numsortkeys = list_length(groupcls);
5814 sortColIdx = (AttrNumber *) palloc(numsortkeys * sizeof(AttrNumber));
5815 sortOperators = (Oid *) palloc(numsortkeys * sizeof(Oid));
5816 collations = (Oid *) palloc(numsortkeys * sizeof(Oid));
5817 nullsFirst = (bool *) palloc(numsortkeys * sizeof(bool));
5818
5819 numsortkeys = 0;
5820 foreach(l, groupcls)
5821 {
5822 SortGroupClause *grpcl = (SortGroupClause *) lfirst(l);
5823 TargetEntry *tle = get_tle_by_resno(sub_tlist, grpColIdx[numsortkeys]);
5824
5825 if (!tle)
5826 elog(ERROR, "could not retrieve tle for sort-from-groupcols");
5827
5828 sortColIdx[numsortkeys] = tle->resno;
5829 sortOperators[numsortkeys] = grpcl->sortop;
5830 collations[numsortkeys] = exprCollation((Node *) tle->expr);
5831 nullsFirst[numsortkeys] = grpcl->nulls_first;
5832 numsortkeys++;
5833 }
5834
5835 return make_sort(lefttree, numsortkeys,
5836 sortColIdx, sortOperators,
5837 collations, nullsFirst);
5838 }
5839
5840 static Material *
make_material(Plan * lefttree)5841 make_material(Plan *lefttree)
5842 {
5843 Material *node = makeNode(Material);
5844 Plan *plan = &node->plan;
5845
5846 plan->targetlist = lefttree->targetlist;
5847 plan->qual = NIL;
5848 plan->lefttree = lefttree;
5849 plan->righttree = NULL;
5850
5851 return node;
5852 }
5853
5854 /*
5855 * materialize_finished_plan: stick a Material node atop a completed plan
5856 *
5857 * There are a couple of places where we want to attach a Material node
5858 * after completion of create_plan(), without any MaterialPath path.
5859 * Those places should probably be refactored someday to do this on the
5860 * Path representation, but it's not worth the trouble yet.
5861 */
5862 Plan *
materialize_finished_plan(Plan * subplan)5863 materialize_finished_plan(Plan *subplan)
5864 {
5865 Plan *matplan;
5866 Path matpath; /* dummy for result of cost_material */
5867
5868 matplan = (Plan *) make_material(subplan);
5869
5870 /*
5871 * XXX horrid kluge: if there are any initPlans attached to the subplan,
5872 * move them up to the Material node, which is now effectively the top
5873 * plan node in its query level. This prevents failure in
5874 * SS_finalize_plan(), which see for comments. We don't bother adjusting
5875 * the subplan's cost estimate for this.
5876 */
5877 matplan->initPlan = subplan->initPlan;
5878 subplan->initPlan = NIL;
5879
5880 /* Set cost data */
5881 cost_material(&matpath,
5882 subplan->startup_cost,
5883 subplan->total_cost,
5884 subplan->plan_rows,
5885 subplan->plan_width);
5886 matplan->startup_cost = matpath.startup_cost;
5887 matplan->total_cost = matpath.total_cost;
5888 matplan->plan_rows = subplan->plan_rows;
5889 matplan->plan_width = subplan->plan_width;
5890 matplan->parallel_aware = false;
5891 matplan->parallel_safe = subplan->parallel_safe;
5892
5893 return matplan;
5894 }
5895
5896 Agg *
make_agg(List * tlist,List * qual,AggStrategy aggstrategy,AggSplit aggsplit,int numGroupCols,AttrNumber * grpColIdx,Oid * grpOperators,List * groupingSets,List * chain,double dNumGroups,Plan * lefttree)5897 make_agg(List *tlist, List *qual,
5898 AggStrategy aggstrategy, AggSplit aggsplit,
5899 int numGroupCols, AttrNumber *grpColIdx, Oid *grpOperators,
5900 List *groupingSets, List *chain,
5901 double dNumGroups, Plan *lefttree)
5902 {
5903 Agg *node = makeNode(Agg);
5904 Plan *plan = &node->plan;
5905 long numGroups;
5906
5907 /* Reduce to long, but 'ware overflow! */
5908 numGroups = (long) Min(dNumGroups, (double) LONG_MAX);
5909
5910 node->aggstrategy = aggstrategy;
5911 node->aggsplit = aggsplit;
5912 node->numCols = numGroupCols;
5913 node->grpColIdx = grpColIdx;
5914 node->grpOperators = grpOperators;
5915 node->numGroups = numGroups;
5916 node->aggParams = NULL; /* SS_finalize_plan() will fill this */
5917 node->groupingSets = groupingSets;
5918 node->chain = chain;
5919
5920 plan->qual = qual;
5921 plan->targetlist = tlist;
5922 plan->lefttree = lefttree;
5923 plan->righttree = NULL;
5924
5925 return node;
5926 }
5927
5928 static WindowAgg *
make_windowagg(List * tlist,Index winref,int partNumCols,AttrNumber * partColIdx,Oid * partOperators,int ordNumCols,AttrNumber * ordColIdx,Oid * ordOperators,int frameOptions,Node * startOffset,Node * endOffset,Plan * lefttree)5929 make_windowagg(List *tlist, Index winref,
5930 int partNumCols, AttrNumber *partColIdx, Oid *partOperators,
5931 int ordNumCols, AttrNumber *ordColIdx, Oid *ordOperators,
5932 int frameOptions, Node *startOffset, Node *endOffset,
5933 Plan *lefttree)
5934 {
5935 WindowAgg *node = makeNode(WindowAgg);
5936 Plan *plan = &node->plan;
5937
5938 node->winref = winref;
5939 node->partNumCols = partNumCols;
5940 node->partColIdx = partColIdx;
5941 node->partOperators = partOperators;
5942 node->ordNumCols = ordNumCols;
5943 node->ordColIdx = ordColIdx;
5944 node->ordOperators = ordOperators;
5945 node->frameOptions = frameOptions;
5946 node->startOffset = startOffset;
5947 node->endOffset = endOffset;
5948
5949 plan->targetlist = tlist;
5950 plan->lefttree = lefttree;
5951 plan->righttree = NULL;
5952 /* WindowAgg nodes never have a qual clause */
5953 plan->qual = NIL;
5954
5955 return node;
5956 }
5957
5958 static Group *
make_group(List * tlist,List * qual,int numGroupCols,AttrNumber * grpColIdx,Oid * grpOperators,Plan * lefttree)5959 make_group(List *tlist,
5960 List *qual,
5961 int numGroupCols,
5962 AttrNumber *grpColIdx,
5963 Oid *grpOperators,
5964 Plan *lefttree)
5965 {
5966 Group *node = makeNode(Group);
5967 Plan *plan = &node->plan;
5968
5969 node->numCols = numGroupCols;
5970 node->grpColIdx = grpColIdx;
5971 node->grpOperators = grpOperators;
5972
5973 plan->qual = qual;
5974 plan->targetlist = tlist;
5975 plan->lefttree = lefttree;
5976 plan->righttree = NULL;
5977
5978 return node;
5979 }
5980
5981 /*
5982 * distinctList is a list of SortGroupClauses, identifying the targetlist items
5983 * that should be considered by the Unique filter. The input path must
5984 * already be sorted accordingly.
5985 */
5986 static Unique *
make_unique_from_sortclauses(Plan * lefttree,List * distinctList)5987 make_unique_from_sortclauses(Plan *lefttree, List *distinctList)
5988 {
5989 Unique *node = makeNode(Unique);
5990 Plan *plan = &node->plan;
5991 int numCols = list_length(distinctList);
5992 int keyno = 0;
5993 AttrNumber *uniqColIdx;
5994 Oid *uniqOperators;
5995 ListCell *slitem;
5996
5997 plan->targetlist = lefttree->targetlist;
5998 plan->qual = NIL;
5999 plan->lefttree = lefttree;
6000 plan->righttree = NULL;
6001
6002 /*
6003 * convert SortGroupClause list into arrays of attr indexes and equality
6004 * operators, as wanted by executor
6005 */
6006 Assert(numCols > 0);
6007 uniqColIdx = (AttrNumber *) palloc(sizeof(AttrNumber) * numCols);
6008 uniqOperators = (Oid *) palloc(sizeof(Oid) * numCols);
6009
6010 foreach(slitem, distinctList)
6011 {
6012 SortGroupClause *sortcl = (SortGroupClause *) lfirst(slitem);
6013 TargetEntry *tle = get_sortgroupclause_tle(sortcl, plan->targetlist);
6014
6015 uniqColIdx[keyno] = tle->resno;
6016 uniqOperators[keyno] = sortcl->eqop;
6017 Assert(OidIsValid(uniqOperators[keyno]));
6018 keyno++;
6019 }
6020
6021 node->numCols = numCols;
6022 node->uniqColIdx = uniqColIdx;
6023 node->uniqOperators = uniqOperators;
6024
6025 return node;
6026 }
6027
6028 /*
6029 * as above, but use pathkeys to identify the sort columns and semantics
6030 */
6031 static Unique *
make_unique_from_pathkeys(Plan * lefttree,List * pathkeys,int numCols)6032 make_unique_from_pathkeys(Plan *lefttree, List *pathkeys, int numCols)
6033 {
6034 Unique *node = makeNode(Unique);
6035 Plan *plan = &node->plan;
6036 int keyno = 0;
6037 AttrNumber *uniqColIdx;
6038 Oid *uniqOperators;
6039 ListCell *lc;
6040
6041 plan->targetlist = lefttree->targetlist;
6042 plan->qual = NIL;
6043 plan->lefttree = lefttree;
6044 plan->righttree = NULL;
6045
6046 /*
6047 * Convert pathkeys list into arrays of attr indexes and equality
6048 * operators, as wanted by executor. This has a lot in common with
6049 * prepare_sort_from_pathkeys ... maybe unify sometime?
6050 */
6051 Assert(numCols >= 0 && numCols <= list_length(pathkeys));
6052 uniqColIdx = (AttrNumber *) palloc(sizeof(AttrNumber) * numCols);
6053 uniqOperators = (Oid *) palloc(sizeof(Oid) * numCols);
6054
6055 foreach(lc, pathkeys)
6056 {
6057 PathKey *pathkey = (PathKey *) lfirst(lc);
6058 EquivalenceClass *ec = pathkey->pk_eclass;
6059 EquivalenceMember *em;
6060 TargetEntry *tle = NULL;
6061 Oid pk_datatype = InvalidOid;
6062 Oid eqop;
6063 ListCell *j;
6064
6065 /* Ignore pathkeys beyond the specified number of columns */
6066 if (keyno >= numCols)
6067 break;
6068
6069 if (ec->ec_has_volatile)
6070 {
6071 /*
6072 * If the pathkey's EquivalenceClass is volatile, then it must
6073 * have come from an ORDER BY clause, and we have to match it to
6074 * that same targetlist entry.
6075 */
6076 if (ec->ec_sortref == 0) /* can't happen */
6077 elog(ERROR, "volatile EquivalenceClass has no sortref");
6078 tle = get_sortgroupref_tle(ec->ec_sortref, plan->targetlist);
6079 Assert(tle);
6080 Assert(list_length(ec->ec_members) == 1);
6081 pk_datatype = ((EquivalenceMember *) linitial(ec->ec_members))->em_datatype;
6082 }
6083 else
6084 {
6085 /*
6086 * Otherwise, we can use any non-constant expression listed in the
6087 * pathkey's EquivalenceClass. For now, we take the first tlist
6088 * item found in the EC.
6089 */
6090 foreach(j, plan->targetlist)
6091 {
6092 tle = (TargetEntry *) lfirst(j);
6093 em = find_ec_member_for_tle(ec, tle, NULL);
6094 if (em)
6095 {
6096 /* found expr already in tlist */
6097 pk_datatype = em->em_datatype;
6098 break;
6099 }
6100 tle = NULL;
6101 }
6102 }
6103
6104 if (!tle)
6105 elog(ERROR, "could not find pathkey item to sort");
6106
6107 /*
6108 * Look up the correct equality operator from the PathKey's slightly
6109 * abstracted representation.
6110 */
6111 eqop = get_opfamily_member(pathkey->pk_opfamily,
6112 pk_datatype,
6113 pk_datatype,
6114 BTEqualStrategyNumber);
6115 if (!OidIsValid(eqop)) /* should not happen */
6116 elog(ERROR, "missing operator %d(%u,%u) in opfamily %u",
6117 BTEqualStrategyNumber, pk_datatype, pk_datatype,
6118 pathkey->pk_opfamily);
6119
6120 uniqColIdx[keyno] = tle->resno;
6121 uniqOperators[keyno] = eqop;
6122
6123 keyno++;
6124 }
6125
6126 node->numCols = numCols;
6127 node->uniqColIdx = uniqColIdx;
6128 node->uniqOperators = uniqOperators;
6129
6130 return node;
6131 }
6132
6133 static Gather *
make_gather(List * qptlist,List * qpqual,int nworkers,int rescan_param,bool single_copy,Plan * subplan)6134 make_gather(List *qptlist,
6135 List *qpqual,
6136 int nworkers,
6137 int rescan_param,
6138 bool single_copy,
6139 Plan *subplan)
6140 {
6141 Gather *node = makeNode(Gather);
6142 Plan *plan = &node->plan;
6143
6144 plan->targetlist = qptlist;
6145 plan->qual = qpqual;
6146 plan->lefttree = subplan;
6147 plan->righttree = NULL;
6148 node->num_workers = nworkers;
6149 node->rescan_param = rescan_param;
6150 node->single_copy = single_copy;
6151 node->invisible = false;
6152
6153 return node;
6154 }
6155
6156 /*
6157 * distinctList is a list of SortGroupClauses, identifying the targetlist
6158 * items that should be considered by the SetOp filter. The input path must
6159 * already be sorted accordingly.
6160 */
6161 static SetOp *
make_setop(SetOpCmd cmd,SetOpStrategy strategy,Plan * lefttree,List * distinctList,AttrNumber flagColIdx,int firstFlag,long numGroups)6162 make_setop(SetOpCmd cmd, SetOpStrategy strategy, Plan *lefttree,
6163 List *distinctList, AttrNumber flagColIdx, int firstFlag,
6164 long numGroups)
6165 {
6166 SetOp *node = makeNode(SetOp);
6167 Plan *plan = &node->plan;
6168 int numCols = list_length(distinctList);
6169 int keyno = 0;
6170 AttrNumber *dupColIdx;
6171 Oid *dupOperators;
6172 ListCell *slitem;
6173
6174 plan->targetlist = lefttree->targetlist;
6175 plan->qual = NIL;
6176 plan->lefttree = lefttree;
6177 plan->righttree = NULL;
6178
6179 /*
6180 * convert SortGroupClause list into arrays of attr indexes and equality
6181 * operators, as wanted by executor
6182 */
6183 dupColIdx = (AttrNumber *) palloc(sizeof(AttrNumber) * numCols);
6184 dupOperators = (Oid *) palloc(sizeof(Oid) * numCols);
6185
6186 foreach(slitem, distinctList)
6187 {
6188 SortGroupClause *sortcl = (SortGroupClause *) lfirst(slitem);
6189 TargetEntry *tle = get_sortgroupclause_tle(sortcl, plan->targetlist);
6190
6191 dupColIdx[keyno] = tle->resno;
6192 dupOperators[keyno] = sortcl->eqop;
6193 Assert(OidIsValid(dupOperators[keyno]));
6194 keyno++;
6195 }
6196
6197 node->cmd = cmd;
6198 node->strategy = strategy;
6199 node->numCols = numCols;
6200 node->dupColIdx = dupColIdx;
6201 node->dupOperators = dupOperators;
6202 node->flagColIdx = flagColIdx;
6203 node->firstFlag = firstFlag;
6204 node->numGroups = numGroups;
6205
6206 return node;
6207 }
6208
6209 /*
6210 * make_lockrows
6211 * Build a LockRows plan node
6212 */
6213 static LockRows *
make_lockrows(Plan * lefttree,List * rowMarks,int epqParam)6214 make_lockrows(Plan *lefttree, List *rowMarks, int epqParam)
6215 {
6216 LockRows *node = makeNode(LockRows);
6217 Plan *plan = &node->plan;
6218
6219 plan->targetlist = lefttree->targetlist;
6220 plan->qual = NIL;
6221 plan->lefttree = lefttree;
6222 plan->righttree = NULL;
6223
6224 node->rowMarks = rowMarks;
6225 node->epqParam = epqParam;
6226
6227 return node;
6228 }
6229
6230 /*
6231 * make_limit
6232 * Build a Limit plan node
6233 */
6234 Limit *
make_limit(Plan * lefttree,Node * limitOffset,Node * limitCount)6235 make_limit(Plan *lefttree, Node *limitOffset, Node *limitCount)
6236 {
6237 Limit *node = makeNode(Limit);
6238 Plan *plan = &node->plan;
6239
6240 plan->targetlist = lefttree->targetlist;
6241 plan->qual = NIL;
6242 plan->lefttree = lefttree;
6243 plan->righttree = NULL;
6244
6245 node->limitOffset = limitOffset;
6246 node->limitCount = limitCount;
6247
6248 return node;
6249 }
6250
6251 /*
6252 * make_result
6253 * Build a Result plan node
6254 */
6255 static Result *
make_result(List * tlist,Node * resconstantqual,Plan * subplan)6256 make_result(List *tlist,
6257 Node *resconstantqual,
6258 Plan *subplan)
6259 {
6260 Result *node = makeNode(Result);
6261 Plan *plan = &node->plan;
6262
6263 plan->targetlist = tlist;
6264 plan->qual = NIL;
6265 plan->lefttree = subplan;
6266 plan->righttree = NULL;
6267 node->resconstantqual = resconstantqual;
6268
6269 return node;
6270 }
6271
6272 /*
6273 * make_project_set
6274 * Build a ProjectSet plan node
6275 */
6276 static ProjectSet *
make_project_set(List * tlist,Plan * subplan)6277 make_project_set(List *tlist,
6278 Plan *subplan)
6279 {
6280 ProjectSet *node = makeNode(ProjectSet);
6281 Plan *plan = &node->plan;
6282
6283 plan->targetlist = tlist;
6284 plan->qual = NIL;
6285 plan->lefttree = subplan;
6286 plan->righttree = NULL;
6287
6288 return node;
6289 }
6290
6291 /*
6292 * make_modifytable
6293 * Build a ModifyTable plan node
6294 */
6295 static ModifyTable *
make_modifytable(PlannerInfo * root,CmdType operation,bool canSetTag,Index nominalRelation,List * partitioned_rels,List * resultRelations,List * subplans,List * withCheckOptionLists,List * returningLists,List * rowMarks,OnConflictExpr * onconflict,int epqParam)6296 make_modifytable(PlannerInfo *root,
6297 CmdType operation, bool canSetTag,
6298 Index nominalRelation, List *partitioned_rels,
6299 List *resultRelations, List *subplans,
6300 List *withCheckOptionLists, List *returningLists,
6301 List *rowMarks, OnConflictExpr *onconflict, int epqParam)
6302 {
6303 ModifyTable *node = makeNode(ModifyTable);
6304 List *fdw_private_list;
6305 Bitmapset *direct_modify_plans;
6306 ListCell *lc;
6307 int i;
6308
6309 Assert(list_length(resultRelations) == list_length(subplans));
6310 Assert(withCheckOptionLists == NIL ||
6311 list_length(resultRelations) == list_length(withCheckOptionLists));
6312 Assert(returningLists == NIL ||
6313 list_length(resultRelations) == list_length(returningLists));
6314
6315 node->plan.lefttree = NULL;
6316 node->plan.righttree = NULL;
6317 node->plan.qual = NIL;
6318 /* setrefs.c will fill in the targetlist, if needed */
6319 node->plan.targetlist = NIL;
6320
6321 node->operation = operation;
6322 node->canSetTag = canSetTag;
6323 node->nominalRelation = nominalRelation;
6324 node->partitioned_rels = partitioned_rels;
6325 node->resultRelations = resultRelations;
6326 node->resultRelIndex = -1; /* will be set correctly in setrefs.c */
6327 node->rootResultRelIndex = -1; /* will be set correctly in setrefs.c */
6328 node->plans = subplans;
6329 if (!onconflict)
6330 {
6331 node->onConflictAction = ONCONFLICT_NONE;
6332 node->onConflictSet = NIL;
6333 node->onConflictWhere = NULL;
6334 node->arbiterIndexes = NIL;
6335 node->exclRelRTI = 0;
6336 node->exclRelTlist = NIL;
6337 }
6338 else
6339 {
6340 node->onConflictAction = onconflict->action;
6341 node->onConflictSet = onconflict->onConflictSet;
6342 node->onConflictWhere = onconflict->onConflictWhere;
6343
6344 /*
6345 * If a set of unique index inference elements was provided (an
6346 * INSERT...ON CONFLICT "inference specification"), then infer
6347 * appropriate unique indexes (or throw an error if none are
6348 * available).
6349 */
6350 node->arbiterIndexes = infer_arbiter_indexes(root);
6351
6352 node->exclRelRTI = onconflict->exclRelIndex;
6353 node->exclRelTlist = onconflict->exclRelTlist;
6354 }
6355 node->withCheckOptionLists = withCheckOptionLists;
6356 node->returningLists = returningLists;
6357 node->rowMarks = rowMarks;
6358 node->epqParam = epqParam;
6359
6360 /*
6361 * For each result relation that is a foreign table, allow the FDW to
6362 * construct private plan data, and accumulate it all into a list.
6363 */
6364 fdw_private_list = NIL;
6365 direct_modify_plans = NULL;
6366 i = 0;
6367 foreach(lc, resultRelations)
6368 {
6369 Index rti = lfirst_int(lc);
6370 FdwRoutine *fdwroutine;
6371 List *fdw_private;
6372 bool direct_modify;
6373
6374 /*
6375 * If possible, we want to get the FdwRoutine from our RelOptInfo for
6376 * the table. But sometimes we don't have a RelOptInfo and must get
6377 * it the hard way. (In INSERT, the target relation is not scanned,
6378 * so it's not a baserel; and there are also corner cases for
6379 * updatable views where the target rel isn't a baserel.)
6380 */
6381 if (rti < root->simple_rel_array_size &&
6382 root->simple_rel_array[rti] != NULL)
6383 {
6384 RelOptInfo *resultRel = root->simple_rel_array[rti];
6385
6386 fdwroutine = resultRel->fdwroutine;
6387 }
6388 else
6389 {
6390 RangeTblEntry *rte = planner_rt_fetch(rti, root);
6391
6392 Assert(rte->rtekind == RTE_RELATION);
6393 if (rte->relkind == RELKIND_FOREIGN_TABLE)
6394 fdwroutine = GetFdwRoutineByRelId(rte->relid);
6395 else
6396 fdwroutine = NULL;
6397 }
6398
6399 /*
6400 * Try to modify the foreign table directly if (1) the FDW provides
6401 * callback functions needed for that, (2) there are no row-level
6402 * triggers on the foreign table, and (3) there are no WITH CHECK
6403 * OPTIONs from parent views.
6404 */
6405 direct_modify = false;
6406 if (fdwroutine != NULL &&
6407 fdwroutine->PlanDirectModify != NULL &&
6408 fdwroutine->BeginDirectModify != NULL &&
6409 fdwroutine->IterateDirectModify != NULL &&
6410 fdwroutine->EndDirectModify != NULL &&
6411 withCheckOptionLists == NIL &&
6412 !has_row_triggers(root, rti, operation))
6413 direct_modify = fdwroutine->PlanDirectModify(root, node, rti, i);
6414 if (direct_modify)
6415 direct_modify_plans = bms_add_member(direct_modify_plans, i);
6416
6417 if (!direct_modify &&
6418 fdwroutine != NULL &&
6419 fdwroutine->PlanForeignModify != NULL)
6420 fdw_private = fdwroutine->PlanForeignModify(root, node, rti, i);
6421 else
6422 fdw_private = NIL;
6423 fdw_private_list = lappend(fdw_private_list, fdw_private);
6424 i++;
6425 }
6426 node->fdwPrivLists = fdw_private_list;
6427 node->fdwDirectModifyPlans = direct_modify_plans;
6428
6429 return node;
6430 }
6431
6432 /*
6433 * is_projection_capable_path
6434 * Check whether a given Path node is able to do projection.
6435 */
6436 bool
is_projection_capable_path(Path * path)6437 is_projection_capable_path(Path *path)
6438 {
6439 /* Most plan types can project, so just list the ones that can't */
6440 switch (path->pathtype)
6441 {
6442 case T_Hash:
6443 case T_Material:
6444 case T_Sort:
6445 case T_Unique:
6446 case T_SetOp:
6447 case T_LockRows:
6448 case T_Limit:
6449 case T_ModifyTable:
6450 case T_MergeAppend:
6451 case T_RecursiveUnion:
6452 return false;
6453 case T_Append:
6454
6455 /*
6456 * Append can't project, but if an AppendPath is being used to
6457 * represent a dummy path, what will actually be generated is a
6458 * Result which can project.
6459 */
6460 return IS_DUMMY_APPEND(path);
6461 case T_ProjectSet:
6462
6463 /*
6464 * Although ProjectSet certainly projects, say "no" because we
6465 * don't want the planner to randomly replace its tlist with
6466 * something else; the SRFs have to stay at top level. This might
6467 * get relaxed later.
6468 */
6469 return false;
6470 default:
6471 break;
6472 }
6473 return true;
6474 }
6475
6476 /*
6477 * is_projection_capable_plan
6478 * Check whether a given Plan node is able to do projection.
6479 */
6480 bool
is_projection_capable_plan(Plan * plan)6481 is_projection_capable_plan(Plan *plan)
6482 {
6483 /* Most plan types can project, so just list the ones that can't */
6484 switch (nodeTag(plan))
6485 {
6486 case T_Hash:
6487 case T_Material:
6488 case T_Sort:
6489 case T_Unique:
6490 case T_SetOp:
6491 case T_LockRows:
6492 case T_Limit:
6493 case T_ModifyTable:
6494 case T_Append:
6495 case T_MergeAppend:
6496 case T_RecursiveUnion:
6497 return false;
6498 case T_ProjectSet:
6499
6500 /*
6501 * Although ProjectSet certainly projects, say "no" because we
6502 * don't want the planner to randomly replace its tlist with
6503 * something else; the SRFs have to stay at top level. This might
6504 * get relaxed later.
6505 */
6506 return false;
6507 default:
6508 break;
6509 }
6510 return true;
6511 }
6512